Brendon Rogers is mid-way through his Swansea project, otherwise he'd be my (realistic) ideal candidate. Plays to his ideology of passing and moving and has shown he has the knack of making it work, not only on a budget, but at the highest levels too.
Lambert has arguably the best record of any up-and-coming manager, in fact it's very impressive, and his tactical awareness is very good. Unlike Rogers he plays to strengths rather than a die hard philosophy.
Martinez had done well keeping Wigan in the top flight recently, a challenge I think would have been beyond most managers, possibly the hardest job in English football at the moment. His CV puts him in the promising young manager category, he's likeable, articulate and seems driven.
Poyet, lacks top flight experience at managerial level, seems to be doing quite well, but it's possibly too soon for him.
edit - meant to post in the 'Who do you want as next Villa manager??' thread.