Shannon, I've definitely felt rattled, but not horribly so on parts of the trail, and I'm riding aluminum, albeit with 25s rather than the 23s that came with your bike. (No, I haven't changed them yet.
I'm riding 25s now.. Tho I do weight a tad more then you do (dang feather-weight you So I may feel those a little more-- dunno. North from Milford is the section I'm talking about. Out from Loveland, north is pretty good trail, but your up near YS now.