Just my $0.02. I think your 44mag is plenty for protection. If you want bigger I would skip right over a 454 and go to a 460,480,500. Also you mentioned that you would likely be fishing alone. Of all the things that can be an issue, being alone in such a environment is the most dangerous. Less so in summer, but still major. I dont know how confident or experienced an outdorsemen you are. AK has the potential to wipe you out as quickly as any Grizzly or Polar bear. Coming from MI I would guess your pretty used to the cold and snow.
Concentrated power is not rendered harmless by the good intentions of those who create it.