The 60D is quite a good camera, i'm practically shooting only with it and the only limit that i found is "AI-Servo" focusing the flying birds, something that this camera isn't build for !

In my opinion, if you "feel" to change but you don't want to go full sport\bird hunting, you should safe some money and go with a 6D full frame, and keep the 60D as backup or second body - the 7DMkII is not the evolution you want.

The 17-55 f2.8 is a really good lens too