Last season, my biggest concern was killing one farther in than I could pack out. My second was running into a mother bear with cubs.
I managed to find out that ~3 miles is doable for one guy in three trips, but I think 5 would have been my limit. I also found out what it feels like to meet that mother bear... Thankfully, she didn't decide I was a threat...
This year, I'm going with more of a "just hunt and find a way" approach... And I'm taking bear spray.
My question is, how do you judge just how far you walked without GPS tracking? I calculated my pack trip from the map plus a little extra for elevation. My general experience has been that most guys overestimate the amount of walking they do.