I don't think there is a clear favourite for the men's or the women's. Hopefully Federer keeps up his 2014 form which still isn't his best, Nadal hasn't been playing his best but is probably on the rise from injury, Murray was improving as well from memory and I'm not too sure Djokovic. Maybe one of the up and comers can take it out.
I really don't know about the women's side
I just watched the Kokkinakis match and he saved masses of match points. awesome stuff.