Really? Everyone should enjoy the same aspects of the game as you? SWAT was a godsend in Reach when broken AA's and grenades were a huge issue. It's a game of speed and reflexes, a game of skill with no other variables muddying the water. Not for everybody but it sure as heck has it's place.
Why would it be? They are balanced on the two maps I've seen them on, not hard to take out. The one vehicle I don't feel belongs in MP as fun as it is to use, is the Gauss Hog. That thing kills too much, too fast. A team gets the Gauss and Scorpion on the same map? Good bye rival team.
I went 19-2 on Complex. It's not that it's hard or I'm not good at it. I just find it really stale. Halo gameplay has so much more to offer then peak-a-boo shooting ala COD.