The new keymod XCR should solve a bit of the weight issue but the shorter length of the RFB makes it a better choice for hunting. You can make better off hand shors because the weight is closer to you and you can sholder it for longer periods of time while keeping it steady. For stalking it is easier to go through brush and does not get snagged on brush as easy making it great for dense brush areas.
I have managed MOA and a few Sub MOA 3 shot groups with the RFB using premium factory ammo with 5 shot or more groups opening up to the 1.5 MOA range, something I have not been able to do with the M.
Another rifle to consider would be the FNAR heavy/Browning hog stalker if you are set on a semi 308