Chess.com had a wonderful Game of the Week a few weeks back, which showcased the promise of Hypermodern play. I tried it in this game, but got all tied up. I could really use some help...

I think you should've played 21 gf.  Once you allowed his knight(s) to get hold of e5, your position was suspect.  And after all, you did manage to get a draw out of that endgame (so things could be worse).