1. Agori.

2. Oh, probably, but probably not until it gets to the vehicles. Speaking of which, I wonder why Perditus pilots the Thornatus instead of Metus? And exactly what role does Telluris play...?
3. Skopio's for sure, a transformer, even if the second form is a scorpion or so, is awesome. The whacking arms of the Toa from the Mata to the Metru are cool too, and have to rank somewhere. The Bohrok's neck smashing was epic fun too, but probably doesn't compare to other functions. Boxor's punching actions looked cool too, but I'm not sure. And rivaling the Skopio would probably be the Manas Crabs' remote controled sets.