There could be more, we haven't heard anything yet. I wouldn't expect to see "bugs/AI fixed""Save/load problem resolved "campaign battle replays" in an MTV style commercial.

It's also not a mod. And it's also not a new game. It's an add-on pack. Many of these are just extra weapons, items, levels,missions etc. Some have new "features", but this is certainly not an absolute requirement. Heck, when you buy extra packs or figures for table-top gaming, you're not getting extra "features", but it makes it fun. I love having new choices or continuing the story a little bit more. I would not be disappointed if I only had new things to play with or new places to play on and not new ways to play as well.

Don't buy it then. Buy a brand new game. I think it might be fun. Wait and see. It's not like MI and VI were sold on the bug-fixes/menu tweaks. You found out after you installed it. Right now the mags just want to tell you about the expansion itself, not the game patch that comes with it.