Honestly, most that stuff should've been in the game already. One thing that's going to piss a lot gamers off more than a postponed release date is finding out they're going to have to pay extra for something that should've been in the game already. Kinda like what Rockstar Games did with Midnight Club: LA, launched that game with NO buyable/drivable trucks, then releasing a paid DLC with only 2 land rovers and some cars. I'm pretty sure other game developers have done this, but Bungie and R* Games are the only ones I can think of right now.
Anyways, that's just my opinion.