RE: lightest load for 270wsm
I wouldn't worry about the recoil of the 270 WSM. I just broke my new XCR last week. The recoil really is tolerable.
I would stick with the 130gr. Federal makes a 130 grain with a Nosler Partition as well as Barnes TSX, both will work well.
As far as the ballistic tip, I think they work fine. My father took a buck last year with his 270WSM at about 50 yards with a ballistic tip and the bullet performed very well.