85s at 3800+ turn the 270 into a 220 Swift on steroids. 110 ttsxs at 3400 make for a flat shooting all around load. RE26 and heavies like the 145 eldx or even the 170 Berger (wouldn't be a bit surprised if your rifle will spin them) will stretch its legs. Standard 130/140/150s on top of 4831 for a no nonsense, time tested load. All with the ability to shoot cheap factory ammo that is designed for the cartridge's velocity window, that can be found in about any backwater town. The 270 is an absolutely superb round.

Also, most of your choices for other rounds really won't work very well with the action. Action is too long to be ideal, or wrong bolt face. And the 6.5-284 won't add anything practical over what you have.