Uhg, I don't feel like reading through a bunch of pages of this, but in one of the CT endings, Glenn is ACTUALLY reverted to human form and pops out of the gate. He looks freaking awesome. Lucca and Marle go: Is that Frog?!" or something to that effect.
The ending is one where you don't save Crono. (Oh and I killed Magus)
Certainly. In fact, it figures on the picture on the left for anyone that has 500-600 posts, I think it is. Check out DarkGizmo in an earlier post: he's at that point. Moroever, Crimson Echoes will feature a playable Glenn in human form, using that sprite.