I, for one, am mostly pleased. I like Vaughn and really liked First Class. But I”m not quite sure if this really needs a sequel. It might have worked better as a standalone entry in the series. This is not a popular opinion, but personally I would have liked for them to continue the X-Men Origins line of thinking, and give some of the more interesting characters in the X-Men universe a platform.
X-Men Origins Wolverine is a guilty pleasure of mine and these films could still benefit from the period setting. Each one could focus on a different period. Gambit’s origin could be set in New Orleans in the 70s, which could be very cool. The only problem is that there aren’t enough bankable characters with mainstream appeal for the studios to take a risk on. I’m still holding out for that Deadpool movie though.