First off let me answer your question then I will give my opinion.

A: yes, the 308 is very well suited for what you want.

O: I would take your 270 because you already own it. Then I would purchase a caliber that doesn't overlap nearly as much for my new rifle. There is basically nothing the 308 can do that the 270 can't. Therefore I think that its a lateral move. think about what other kind of hunting you may do. If you think you may hunt larger game then buy the ultra, or a 338, or the new 325 wsm etc. If smaller animals,at longer ranges or varmint hunting will be more the norm then buy something like the 25-06, 243, 223or 22-250 etc