I'd go with whatever 6.5 Creedmoor floats your boat. One of the advantages of high-BC 6.5mm bullets is they provide the same downrange performance as conventional spitzers in with less recoil. High-BC 140's from the Creedmoor started at 2750 basically match the .270 Winchester in velocity with conventional 140's started at 30000 at around 350 yards--and beat the .270 noticeably in wind-drift at any range, with 2/3 the recoil. A Creedmoor would fill your slot between the .22-250 and .30-06 very well.
