I'm not saying hedge out the people that want to do their dialog, but for the people that either can't or don't want to, there is the option of their dialog written for them by others and coming to an agreement about it. (I mean, it's not like any of us had much of a say as to what our character designs were either, right? ;P)
@Drake: What season is it? (Or even better, maybe we can vary it up and have it spring/autumn like in the field, blazing sun in the valley, and snowing by the shrine, explaining the weather as one of the problems caused by the wonky Idiot Energy. I actually like this idea.)
I was thinking less Stage 3 and more like like PCB/MoF stage 4, having most of the stage approaching the shrine, then reaching the entrance to the shrine when you get to the boss.
As for the inside of the shrine, I figured that'd be what we'd be doing anyway (and since it's a shrine set in the mountains, the later stages would be deeper and deeper in, but still completely weird until you get to the end which is completely dark and like a void, or however else we want Theorin's stage to be)
EDIT: Drake, about the dialog, i'll have much more time to devote to trying to get people together to do this after next week. Until then, i'd suggest people to brainstorm ideas of how the dialog could flow, or little things to throw into the dialog so there's something to work with. How long is Baity roadtripping for?