Is it possible to escape fate? Well Guts and Caska did (of course they still are being hounded), but remember the Godhand was quite suprised, as well as Zodd. I think that despite it being his destiny, Griffith could have gone against his fate. It would be interesting to see his state of mind...
Can Griffith be redeemed? I would say no. I would say now more than ever he will be pursuing his dream. In his mind he never actually betrayed anyone, so I think we can rule out guilt or remorse. Its too early to start theorizing how the conflict between Guts/Griffith will end up, but I don't...
I can't see much resemblance to Farnese. To be honest, the character looks a bit boyish (or of course if its a boy it would be girlish). It looks like he/she is going to play a fairly big role in the game, based on how much she appeared in the trailer.