I didn't get some things with Hank in this film. I don't think he was 'wasted' in the film, but he was just sort of 'there' for most scenes and he Beasts out when the action needs him to.
He didn't get any emotional arc of his own and he shared a few glances with Raven at some points, but it didn't go anywhere. He's the same character at the end of the film as he was at the start, they didn't go anywhere with his arc. Sure he used the serum at the end so the Sentinal couldn't kill him, but you don't know if Hank learnt anything from the events of the film from Charles etc, even if he learnt anything from the whole 'Mutant and Proud' theme in First Class. That's when you know a character didn't get a satisfying character arc.
I hope he gets more of an arc in Apocalypse and I think Dark Beast is the way to go.
"I would love to do another X-Men," the actor enthused. "I loved playing Beast! I call him the blue guy and it was just a joy for me to be involved in that franchise and so when I heard they were making another one...It was Hugh (Jackman) that I was talking to and he said, 'You're going to be in the next one aren't ya, mate!?!' (Australian accent included). I said I didn't even know about it. So I called Bryan and said, 'Look I understand that you're in a different timeline now and it's the younger Beast, but there's that little coda at the end. So I volunteered my services for it, because I really like being a part of that franchise."