Personally, I foresee a Bone set at some point.. possibly with the Mistlands update, if it's themed the way I think it is.

Obviously, it would probably be a side set like the ones you mention, but the perplexing part is.. what could the set bonus possibly be? The main resource set would just be higher armor and durability compared to Padded, but a new side set?

Fire resist?

Health return on damage/kill?

Causes attacked skeletons to fight for you?

Interesting thoughts indeed.