I reload everything I shoot, so ammo cost can swing wildly there based on component availability. With the 6.5 being a newer cartridge, it's slightly more than 308 generally speaking, but dropping as it gains in popularity.
I'm in WV, which I think is only 2nd to Texas when it comes to guns. If I had a gun in every caliber known to man, i'd fit in here better.
It's not so much felt recoil that i'm after, but I do like the "bastard" rounds because they are fairly uncommon and they are fun to shoot. Truth be told, my favorite gun I own is a Hi-Point for the same reason, it's the red-headed step child of the gun world. People are shocked when they actually go bang for some reason. The internet has them painted as a non-functional useless hunk of metal, but they are some of the most reliable guns I own. Plus the look on everyone's face when they "just have to shoot it" and it works flawlessly every time is worth what I paid for 'em alone.
EDIT: Yeah 22LR is a hoot and for me it would be a close tie with 22LR and my air rifle in 22 as well. Just plain fun.