!.) I think the villains who are the mirror of the hero should be pretty much left to that hero. I don't necessarily mean the Reverse Flash; but their true opposite number, like the Joker. Joker doesn't mix well with other worlds. He has been used with others; but, the end results are usually less satisfying than when he faces Batman. John Byrne threw him in against Superman to basically show he wasn't as big of a threat to him, as he sets up a puzzle, using a fallacy of thinking where lead shielding occurs, to have Superman demonstrate that it made it easier to rescue the person in question since the lead shielding was easier to spot. Similarly, I don't think Joker mixes well with other villains and the times he has it hasn't worked, for me.

2.) I don't mind villains facing other heroes, as long as they are competitive with them. If they are just being thrown in to be squashed by the hero, it doesn't make the hero look any better, especially if that character is shown to be subordinate to the other hero, like Batman. If Blue Beetle easily takes down the Joker or Riddler and Batman struggles, how does that make Batman look? If Batman still is seen to outclass Beetle, then the defeat of the villain carries no weight and looks like a fluke.

Sometimes, introducing a villain to a new hero actually improves things. Kingpin had been exclusively a Spider-Man foe. However, once he was put up against Daredevil, with DD treated in a more serious crime story fashion (rather than swashbuckling wise-cracker), the Kingpin rose in stature. He truly became the Kingpin of New York Crime.

Sometimes, the villain can be an interesting mercenary type, who acts for another foe of a hero. Or, a career criminal tries to pull a heist in a new venue. The first issue of Manhunter, with Mark Shaw, had him hunting down Captain Cold, in Chicago, instead of Central City. Manhunter was a bounty hunter and Cold was at large. He knew from prison that Cold was a Cubs fan and never missed a game, if he could avoid it. Cold was reported to be in the city and he staked out Wrigley Field and catches Len Snart on his way to the game, on the L. Cold tries to flee and pulls out his weapon; but, Manhunter's tech is built around a wider range of combat, while Cold had focused on Flash for so long, he didn't know how to improvise as well as against the Flash. Now, had they brought Cold back, it should be a different story as someone of his caliber shouldn't fall for the same thing, twice.

Some villains are just set up to be punching bags. I don't think anyone ever treated Stilt-Man seriously and he pretty much got whooped by everyone, without much fuss.

I think the current way of doing things shows a lack of skill on the part of editors as much as talent. Decompression and all of that are fine, for someone who knows how to pace a story properly and what the intent of the story. Making everything fit into that model, especially with someone not skilled in the technique as bad editorial work. Not every story has to be 5 or 6 issues long, nor should they be. You don't have to have one big, long story to fill a trade. You can have it be a short story collection, with a theme (or without, even) as that can be just as entertaining, in the right hands.

Whatever you do in any story has to have an underlying reason, just like you need to have a reason for two pro wrestlers to have a match. Even a random match has a reason, like trying to move up in contention for the title, or the chance for a rookie to make a name for themselves. Same for a superhero story, whether it is a standard issue, a chapter in an epic, or a cross-over. Why are these two characters being brought together? If it is just because you want to see them fight, then you better have a good reason for the fight. With the above Manhunter example, the reason is that Manhunter is a bounty hunter. His job is to hunt down and bring fugitive criminals to jail. He is not out to clean up the city or to protect the innocent or act as a symbol. He is a professional doing his job. Captain Cold is a wanted fugitive, so you have an underlying reason for Manhunter to come into conflict with him, instead of the Flash. If it were Superman, you'd need a much bigger reason. Why would Captain Cold mess around in Metropolis, knowing that Superman can do the things that the Flash can and even more? He wouldn't. He's a professional criminal, who is going to weigh the pros and cons of pulling a heist in Superman's territory. For him to do so, there must be a major reward that makes the risk worthwhile. That reward should then make Cold consider how best to accomplish this, with the added danger. He would look for an edge, with Superman, beyond his normal tech. That should be at the heart of the story. If you just have Cold turn up in Metropolis, to steal a shipment of diamonds (ice), then we know how this is going to play out and we drop the comic and pick up another, unless we have a superstar artist and they go nuts with the visuals, to compensate for a weak story. That rarely works for more than an issue.

In reviewing the team-up books at Marvel, I have come across multiple examples of how to do it right and how to churn out a mediocre story for the sake of a monthly title. The memorable ones have underlying reasons for the team-up and for the defeat of the villain(s). The hacks throw two (or more) people together and have a lot of cliched action and then the villain loses, in a by-the-numbers generic plot. The good writers bring the heroes together for a reason, figure out a strategy and then defeat the villain. Marvel Team-Up #48-51 is a perfect example. Bill Mantlo, the writer, often hacked out the stories, with little reason for anything, but every cliched ticked off the list. This one, though, he is in top form. Spidey encounters a bombing, near a Stark facility. He witnesses an explosion and investigates and runs into Stark's security guy, Iron Man. Iron Man reveals a threat, in the form of a warning note and questions Spidey about his presence and knowledge. They are then surprised by Captain Jean DeWolff, who Spidey knows and has worked with. She reveals that she also received a warning note. Now, without DeWolff, you still have a reason for Spidey and Iron Man to team up; but, it's not a strong one. It's Stark property and Iron Man works for Stark. He might take Spidey's assistance, but he doesn't need it. DeWolff gives this a stronger reason for Spidey to remain on the case, since they are allies and she is involved and even targeted, as the first issue plays out. The bomber is revealed as the Wraith and he attacks DeWolff's office and Iron Man is concussed in the explosion and Spidey ends up helpless, before the Wraith's mental powers. Iron Man ends up rescuing Spidey, after he is recovered enough, but the Wraith escapes. Evidence comes forward that the Wraith is related to the death of Jean's brother and that propels the plot forward and there is even the idea that Brian DeWolf might still be alive or have come back from the dead. That brings Dr Strange into things, as they need his help to discern the reality of what happened the night Brian supposedly died. His supernatural powers can reveal the truth, at the scene of the crime. They learn that Brian survived, but was near death and his father and cohorts worked to save him, but an accident left Brian alive, but in a catatonic state, but with a mental link to his father. His father was able to use him like a puppet, to bring vengeance against his daughter, who he considered a traitor to him. Brian's powers are still strong enough to stop Spidey and even Dr Strange; but, Iron Man is able to find a technological solution to defeat Brian's powers, by crafting a helmet that blocks the mental link with his father, removing his control over Brian, reducing him to the pure catatonic state.

So, there is a logical reason for the two heroes to come together and a strong reason for them to collaborate further and for each to need the help of the other, as well as Dr Strange to enter things. They learn more about their enemy and find a weapon to use against him and defeat him. They don't just fight and lose, then have a rematch and win, as in so many other issues, with the status quo being the same, at the end. Everything has a cause and leads to an effect, which causes the next event in the chain, leading to a trial, which brings the final conclusion to things, as Dr Strange proves instrumental in resolving Brian's condition and we get some justice out of his manipulation by his vengeful father.

Now, The Wraith was created specifically for this story, so we don't have a case for a villain to fight a new hero, though the reasoning is the same, since we are bringing other characters into a Spider-Man book for something other than a Lucille Ball plot, where Lucy (Ricardo or Carmichael) meets a celebrity and hilarity ensues. Many crossovers are little more than that. Whether the crossover is between heroes or hero and someone else's villain, to rise above the Lucy plot, you need to have an underlying rationale.

Yes, I like seeing them mix it up. One of John Byrne's first FF stories had the Human Torch up against Hammerhead, a Spider-Man foe. Doc Ock went up against Iron Man in a Marvel Fanfare story, and of course Mr. Fantastic in a memorable FF story (also by Byrne.)

Not sure how the different writing styles would affect this. If editors are doing their jobs, it shouldn't.

He has, but there is still much I think could be done with him. Has he ever fought the Fantastic Four, for instance? Or the Silver Surfer?

It's the off-kilter villains like Despero, Vandal Savage, Per Degaton, Felix Faust and all these weird "immortal" characters that should be used by all. It seems they're locked into the JLA and JSA rather than being used in solo character books instead of being a team book in which everyone has to get together and beat the snot out of.

My first exposure to Vandal Savage was in the Justice League newspaper strip. It only ran briefly in the paper here, unfortunately.