I really have no idea what sells for Criterion, outside of Wes Anderson and Michael Bay movies. I guess maybe some of the Hitchcocks? Repo Man? Probably some of the Kurosawa titles.
It's a good question as to how Criterion mounts some of these projects. They did just release Touki Bouki, so I guess I feel as if anything's possible. But "anything" sometimes proves itself to be the end of the adventure.
If they did Johnnie To movies, I'd like a good disc of Vengeance, where someone on an audio commentary talked about the film being a quasi-sequel to Le Samourai. Everyone I ever spoke with about the film seems to have missed this aspect of the picture--the aspect that makes it most interesting, perhaps. The Mission could really benefit from the Criterion treatment, as could Sparrow or the Election movies--all of which have somewhat low-standard blu-ray releases. It would be interesting to see some of To's earlier work on blu-ray--The Heroic Trio, perhaps, or some of the populist comedies, like The Fun, the Luck and the Tycoon. The Enigmatic Case, To's debut, is actually a picture I wouldn't really care to see rehabilitated--it did close to nothing for me, and it doesn't really interest the way other such debuts do, like Tsui Hark's Butterfly Murders or Patrick Tam's The Sword.
I like Ringo Lam's Victim a whole lot, but I doubt anyone else feels that it deserves criterion treatment.
Pedicab Driver would be a cool one for Criterion to release. Seeing as no one has been able to track it down since the laserdisc days, and seeing that it is Sammo's best film, and that it has a really well-organized collection of themes, there might be both reason for Criterion to take notice and a market for the film if Criterion were to release it. Tsui Hark's The Blade might have some decent interest attached to it, and could certainly prompt a great cover design.
The King Hu films are deserving but likely it won't happen, I think. The rights to the films are in some cases unknown, or contested, and good elements are hard to find. The King Hu Foundation restored The Valiant Ones about 15 years ago, but it could very well be in bad shape again, and the Foundation, last I had heard, had no resources to promote the film or release it in any home video format. I thought I once heard that the rights owner for Dragon Inn and A Touch of Zen was bankrupt. With the resurgence of wuxia movies, there has been plenty of opportunities to promote these movies, but they have never managed to really get seriously released anywhere (minus the old Japanese DVDs and the various dismal tries at A Touch of Zen). It would be interesting to do a pairing of Dragon Inn and Anger, along with the Raymond Lee Dragon Inn. I've heard but have been unable to confirm that the feisty female innkeeper Maggie Cheung plays in the Raymond Lee film is based on a character from Anger--and Anger is an essentially unseeable film. So it would be cool to see the two King Hu films, and then connect the influences to the 90s remake. Kind of like a Killers box set! But I doubt that will happen, either.