Strategy is very much song dependent, it seems. For example, at the beginning of the song, do you try to take all tracks to 4x or do you try to take them to 2x? On some songs, you don't have time to take them all to 4x, at least as far as I can tell, so you go ahead and get that level cap as high as you can right off the bat.
There's strategy in choosing whether or not to bail on a track, when to get multipliers up, and when to deploy power ups. You really have to learn the song first, map out when to deploy a powerup, then "buy" your power up with those stupid coins. Or I could just have it all wrong at this point.
I like the game, but I do think it's missing something from not having three notes. Playing the actual notes is not as fun as planning out your strategy, but the strategy is enough to enjoy it at this price point. And I'll be playing some of the 25 songs in RB3 later.