The relative immobility of people in plate armor is generally highly exaggerated, from what I've been lead to believe, at least. Knights in plate were generally expexted to be able to do cartwheels, leap onto horseback, etc while in armor. I would think that if armor made you that immobile when knocked off a horse, it would have been considered a liability and never be used.
I do hope that all weapons are given fairly equal representation in game, though like others don't think that would be much of an issue considering that Black Isle made it a point to have few swords in PST because of the overrepresentation of swords in many games. That said if I play fighters, I myself am generally a sword (or sometimes spear) and shield type guy.
Also while magic jewelry has a long history in fantasy and myth, I can't help but feel a little odd when my characters go into battle decked out in rings, necklaces and other assorted jewelry.