In terms of drivable platforms, it's one of the reasons I' ve yet to buy the game: It's not that I don't want to drive Surface ships or aircrafts it's just that I don't really want to drive American or Russian ones that much.
As much I always enjoyed the 688 in SC and would like to mess around with the OHP, I would much rather get a Traffie with British voices than more Russian or American stuff, as fun as they are.
I'm probably going to buy the game anyway but I would pay even more for a Royal Navy Add-On or, at a push, a cold war one....I really would.