I believe hes contracted for another season of TW, so any movie projects are filmed around it....
This means he has to choose only roles that fit around this schedule.
He's the biggest star on TW now, and while his loyalty to the show is admirable - his career may well be better served by leaving and making more movies.
He's in his prime years now. Perhaps should be making more of his talent..
You are exactly where I was a couple months ago. I started watching the show only to see Dylan's performance. I'd watch anything from season 3b (episodes 3x13 to 3x24). That's by far the best season and if Dylan had given that caliber of a performance in a high-profile film, he would've been nominated for an oscar, he's that impressive. The first one I ever watched was 3x18 "Riddled". Many would consider that to be the best episode of TW. It plays out like it's own little movie almost, so you don't have to know a lot about the characters' pasts. I was hooked after that.
I also recommend from 3b:
3x22 "De-Void". There is a scene in here that I would consider Dylan's finest moment so far as an actor.
3x18 to 3x24. (3x19 "Lutharia Vulpina" and 3x20 "Echo House" are both pretty awesome, up there with Riddled and Motel California)
Also not from 3b:
3x6 "Motel California" (another episode up there with Riddled. Plays out like it's own little movie as well.)
5x15 "Amplification" (you can kinda jump right into this as well, I feel, and it feels like an Ocean's 11 tribute)
4x7 "Weaponized" (I'm trying to pick out episodes that are fun to watch where you don't have to know too much about the plot)
Are you looking for episodes that just feature awesome acting from Dylan or ones that overall have a good story line to them? I think I recommended a mix of both :)