Take my advice, and don't even consider getting BfME2. It's ONLY good when you mod it HEAVILY.
-No more rohan
-No more walkable walls in non-fortress maps
-Faction uniqueness is non-existent
-stuffed up battalions
-Rock-paper-scissors is LAW
-"build anywhere" is not necessarily a good thing
-feels more like a LotR RTS game rather than an RTS LotR game
The ONLY thing BfME2 has on 1 is better graphics. Every time I try playing 2 I get bored within minutes.
As for the RotWK expansion, EA were INTENT on messing their game up
Seriously. BfME1 is WAY BETTER.