I couldn't actually finish the second one, turned it off after about an hour. I could see they were trying to get at some of the flavour of planetary romance, but the characters and their interactions were so annoying. It was practically Star Wars prequel level.
The first one was watchable with a dull "learn to be a team" plotline, but it's the aesthetic sense I really find troubling. That whole subfranchise is just way too far into cartoon-land for me.
I hear after they wrap the Avengers they're going to phase into Fantastic Four (I'm sure some of the series veterans will be eager to give up their contracts for the most part by now).