What about the chris clone? And Hunk? Any light on that?

I think Hunk was just a placeholder model :p

Chris clone is a mannequin in the first 10 minutes of the game.

So, I can't help but wonder why Jill was the primary character we control in the game. She doesn't have much stake in the overall plot, and it felt like she was just a casual observer the entire time.

It's true that she was long overdue for a game in which she is the primary character we control. But Chris had a very minor role in Revelations as well. In fact, I think Jill in Alternative Edition has longer playtime than Chris does in Revelations.

But, of the three RE4-style games, Leon, Chris and Jill have each had their spotlight. Maybe if Capcom decides to make a sequel to Revelations (i.e. a 3DS/Vita handheld RE), we can finally get a Claire game.

I think if you combine her appearances in Revelations, LIN, DE and ORC it puts her on par with Chris.
Chris and Jill were basically for sales and to set up 6 if nothing else. Nobody would care about this game at all if it was just Parker, Jessica and the others.

It would have been nice if Jill had more ties to Parker or Jessica... Like them being old friends or something.

Also, I noticed a few subtle throwbacks to previous REs in Revelations:

1. The huge tentacle battle and the helicopter boss fight (RE5)
2. Kirk, the chopper pilot, tosses Jill rocket launchers as he waits for the boss to be defeated (RE1)
3. Jill has become immune to yet another viral strain (RE3)
4. Laser room (RE4/movies)
5. Exploding city (RE3)
6. Luxury Ship setting (RE Dead Aim)

That reminds me Kirk made some nice cameo. Wasn't expecting that. :)

Jessica should have been the main character, with Parker as secondary. Jill in this game is plain, they didn't bothered with her besides the plastic surgery.

Playing with Jessica all the game and at the end she betrys Parker and the BSAA, that would be more interesting in my opinion. But probably is too much to ask for Capcom, they can't help to put Jill, Chris or Leon in every frikin game.

They need a beloved character to help the sales of the game.

I would totally get Revelations 2, but If it's Multiplatform, I don't want a version to be better than thr other :/

Would just be Dead Aim 2 to most people. it gives Chris a good connection to the villain, just think about CV if Wesker or Chris wasn't in RE1. nobody would have cared about them or their fight.