While I don't care for the over-reliance on the Batmobile nor the fact that the majority of the "boss fights" were IN the Batmobile, there were some cool things you could do with it.
When I was taking down the Militia checkpoints and watchtowers, on some of them, I found it easier to lure them near the edge and pick them off the the Batmobile's beanbag gun (or whatever it's less than lethal rounds are).
On some of them, I'd ramp the batmobile in and just drive over everyone. Usually, that was a last ditch effort after they had me completely pissed off.