I don't know if anyone theorized about this, but i think in this new arc, TP is gonna be another arc like skypia. it is an isolated place, in the fog, with no WG there, and bounties may not mean anything, though until now we don't know if this place is totally isolated or not.
the main point i would like to adress is the relevance of this arc to the rest of the storyline. in skypia, there were the dials, there was one of those square stones that robin was looking for, and we knew something about roger. i don't know about the stone or roger, but i think that the SH's will power up there to be able to fight BB since we are talking about a strange island with strange creatures and a strange DF that even a logia user as ace couldn't win against