You need to figure out your package the same way they figure out theirs.
Ultimately what you're selling (or leasing, depending on the deal) is not your story or your characters but the underlying media property rights. Artistically your story and characters are your bread and butter, but financially your property rights are the most valuable thing you have. And everybody in the process but you knows it.
These days, giving Wikipedia, IMDB and numerous other websites, it's easy to research any producer who approaches you. You want to know whether they've produced any, what kinds and how much general success and critical response they've had. For instance, Marc Platt Productions, the main production company on "2 Guns" made, among other things, "Drive," so we knew they knew how to make a good crime film. They made "Wanted," so we knew they understood both comics and action. Leaving money out the equation altogether, they still felt like a great fit. You don't necessarily want the hottest production company in town, though that might be where the big money is. (Unless all you want out of it is money, in which case go for the gold.) Unless you've got one hell of a great agent -- and there are screenwriters and novelists on top of their particular mountains who've never had that agent -- you won't be in control of the movie. The producers will be. You want a producer to be a comfortable fit for your property. That's probably the only thing about the adaptation you'll be able to control unless you want to be a producer yourself. That's not a title give up lightly, and it means you'll have to be prepared to do the work required by the title.
If you want control, if you want say over all aspects of the production, save everyone a lot of time and bring it up right away. It's not wrong to want that, but understand that by making a point of it you have basically said, "I never want my character/story/series" used in any other medium. That's okay, maybe you don't. It's your choice. The only real leverage you've got on any offer is your willingness to walk away from it, but you have to understand that opportunity's not necessarily ever swinging back your way if you do.
This is comics, where we all think we're undiscovered genius, but put that aside and try to make a realistic assessment of if you want a media deal (it's okay not to, honest), where your project might fit into the overall cultural scheme of things (you might really think your zombie idea is sweet, but if the market's flooded with zombie properties that's trouble for you, but your transvestite priest who moonlights as a cop-killing stripper drawn as funny animal comics might be seen as a little riskier than anyone thinks a studio will want to put money behind; doesn't mean either of them shouldn't be done -- in comics, if you can find a publisher -- but it'll likely limit the number of media offers you'll get to entertain), and how directly involved you have to be.
I don't necessarily recommend it for anyone else, but the path I've taken with the properties I control is to hook up with a small handful of producers and publishers I trust, who know me, my interests and limits, and who I know I can depend on to look out for my interests, but not to the point of stupidity. Because what I want is this: it all. I want to be able to create what I want, and get paid for it. And I don't especially care what the conduit for getting paid is. If I can sell enough comics to keep my dog in kibble, great. If I can get media deals that pick up the slack and take the need for one crappy work-for-hire assignment after another (unless I feel like doing one) out of the equation, man, I'm there. Through my proxies (who, I'm happy to say, are also my friends) I don't have to deal with lawyers, agents, managers moneymen or any of the other myriad parties to deals.
And I do understand that though "2 Guns" worked out great across the board, and the other projects based on my work are apparently moving ahead fine, there's always a chance that sooner or later something will be done I'm not going to like. If that's a risk you're not willing to take, don't. But the money will still be there, and I will create again.
It comes down to what you want. Figure out what you want.
The good news is you don't have to rush into anything, because:
The "comic book movie" isn't going away.
It has gotten to the point whenever a "comic book movie" comes out, articles, tweets and blogposts start flying wondering whether "the comic book movie" has reached saturation point.
It hasn't, and it won't.
The superhero film might, depending on how it's played. For some reason the more successful they are the more the death of the superhero film is posited. "Iron Man 3" and "Man of Steel" both started that gossip wagging, and, yeah, there's some reason for concern over the market viability of "Guardians of the Galaxy"; it'll be the first real test of Marvel's ability to market the Marvel name over all other factors. The biggest problem of the superhero film is the biggest problem of modern superhero comics: they increasingly orbit madly around impending apocalypses, and how much more more apocalyptic can they get. What can possibly come from a "Justice League" movie that filmgoers didn't already get from "The Avengers," besides a different assortment of costumes? As superhero films get bigger, there's an increasing narrowness to their focus that stands a pretty decent chance of ultimately impaling them.
But the superhero film is only a fraction of the "comic book films" in existence. "The Walking Dead" comes from comic books. Does anyone seriously think "The Walking Dead" is teetering on the edge of extinction? On the horizon are "Kick-Ass 2," the "300" sequel and, of course, on August 2, "2 Guns," and those are just the "comic book movies" I can recall off the top of my head.
The difference between them and "Man of Steel" is that much of their audience will go to them without realizing they were derived from comic books, and they likely wouldn't care even if they knew. Does anyone seriously go to any movie because it's a "comic book movie," or do they go because there's an actor or director or storyline that interests them, or just because the trailer makes it look like a hell of a lot of fun?
Like I said, much of the power structure and talent pool of Hollywood, and increasingly more of the decision makers all the time, is now composed of people who grew up reading comics, maybe even wanted to create comics, and went into film and TV. Whereas once comics were a rare and suspect source of material for the town, they're now integrated to a level the comics industry largely refuses to believe. Producers haunt (or send their assistants to haunt) Los Angeles comics shops every release day, looking for that next potential big property. Comics are now part of the town's firmament, and while there's still some veneer of newness to them they've largely become just more source material, like novels, rock songs, video games, old movies, old radio shows, theatrical productions, and anything else Hollywood has ever gone to, and continues to go to, for source material.
We got what we wanted. Comics are mainstream now. The "comic book film" is in no more danger than "the novel film." It's not going away. The only real variable left is how we decide to deal with it, and that's something everyone in comics gets to decide for themselves.
Final column coming later this week, and "2 Guns" (directed by Baltasar Kormákur and starring Denzel Washington, Mark Wahlberg, Paul Patton, Bill Paxton, Edward James Olmos and James Marsden, if somehow you missed it) opens Friday, August 2 at a theater near you. Be there.
Replies, mash notes, hate mail, etc. can be sent to email@example.com. Anyone who wants face time can find me at WizardWorld Chicago August 8-11. I'll have my own table, so check the convention book for location. See you there.