So Battalion Wars 2 is pretty awesome. The only real gripe I have with the game, aside from Nintendo's stubbornness with some online features, is the fact that you can still lock on to your on units. This is so you can lock on to a unit to transfer your control to it, but you can just use the D-pad to select a unit type then hold A to do it which is easier and faster. It can be incredibly frustrating trying to target in a group of 20+ troops.
That aside, the game is an overall improvement from the first. Online is incredibly fun.