Posted: 2/2/16 at 11:47pm
I don't think it's that he can't play a leading role, it's that he struggles with playing dangerous, playing the bad boy.
That doesn't mean he has to play the boy next door all the time. His two best performances in my opinion were Gabe in Next to Normal and Enjolras in Les Miserables, neither of which fit that stereotype. The latter role increased his fan following drastically, despite it being incredibly minor. There were far more people obsessing over Tveit online after the Les Mis movie than there was Eddie Redmayne, despite Marius being a much bigger character. That clearly shows that he can and does have plenty of charisma in certain roles.
However, his two weakest roles from the ones I've seen are Roger in Rent and Danny in Grease, where he plays the reformed bad boy rocker type. Not to say he does a bad job of either, I think it's just the one type of role he shouldn't play. I thought he did the absolute best he could as Danny but his look just didn't suit it. I also think John Travolta gave a performance in the movie that is by far the most iconic of the entire movie's cast, and people who have only been exposed to Grease through the movie were always going to have an issue with whoever played Danny.