McBain,

Given your terrain and with larger game such as elk and black bear on the target list, I'd nudge the Casull ahead of the .44. I've handled the BFR's, but have no firsthand knowledge of them myself other than some gun shop pawing. However, I can comment on the FA's. Since mine would wear optics, I'd go with a 10" as first choice, with 7.5" as a slightly more portable second.

My vote on optics would be a Bushnell Elite 2-6 or 2.5-8 Leupold in the variables, but a fixed 4X can be surprisingly versatile, even at distance.

Keep quality jacketed bullets such as Swift A-Frames (265/300/325), XTP Mags (300), Nosler Partitions (260/300) (discontinued, but can be found sparingly still) and the Barnes XPB's (250) in mind. These premium bullets have been used by members here to take Alaskan bears and African plains and dangerous game in the recent seasons, and would serve you well too.