BC2 has some very large maps. Rush actually shows the full size of many of them. Conquest versions just chop off the two ends.
That said some of the Conquest maps are still pretty huge, especially if you don't have a vehicle. And I believe there are server side switches which can use larger versions of them much like in BF2.
BC2's single player has two epic moments (that like two in MoH, I think top the CoD campaigns since 2), coming down the hill during the blizzard, and then the Bolivian salt lake semi-open world part.
BC2's main draw is that, outside of some quirks in the unlock trees, it's just incredibly well balanced even when vehicles are active, and DICE admits that this happened kinda by accident. Which is why no BC3 yet, they can't "re-create" it. But they know how to do old Battlefield.
Arica Harbor Rush when one side constantly loses until the bridge (since nobody ever seems to know you can go under it) and then they push you back into the town and the whole area gets leveled.

The two or three segment Rush maps stink, but the four or five segment ones make the mode work. It even makes Metro palatable when you finally get out of the tunnels. (And retrospectively makes that hell slog seem like an accomplishment.)