I have always wanted to have an AR character but it just never works out. I never cared much about the damage dealing issue, one can make just about anything work in the game, after all I have three DP Blasters and enjoy them all. I just had a problem with certain powers and the immersion breaking aspect of them. And when you customize the weapon the immersion break becomes even more pronounced. To me I could pretend that when I was using Sniper Rifle that was when I was actually stopping, aiming and firing as opposed to standard AR use (suppressive fire, spray and pray). I could say that the M30 Grenade and to a lesser extent the Buckshot were fired from a shotgun type barrel underslung which also explained to lower damage grenade (perhaps only 25mm vice 40mm).
But Incinerate and effing Flamethrower just broke everything for me and they only work on that ludicrous, inane M63 Frankengun because of the super soaker can on it. Change it to a thermobaric grenade; whump--boom--burn patch then I can work with ignite but flamethrower . . . le sigh. Two powers shouldn't spoil the whole set and for most people probably doesn't, but for me, in this case, it wasn't the "anemic damage" it was the two burny powers.
This is of course why I stayed out of the AR change fight for the most part because my reasons are not ground in data or results they were my opinion skewed by my quirks.
Then again if I was the person who made those decisions, a lot of people would be angry with them because yeah, I have a lot of quirks. 🙂