Just a note here, I don't necessarily condone declawing, but it was my decision for my reasons. My cats are not outside alone, but they did learn to adapt. They all used their teeth and hind claws much better. In fact, the first one I had could climb trees and telephone poles when he weighed 25 lbs. and had every dog in the neighborhood afraid of him only because he learned to appear vicious. He was far from that. He was also a good moler. I had moles, not mice. I even found him on top of my fridge one time and the only possible way to get there was straight up from the floor. Without claws to grab the top of the door, he must have used toe strength.
Maybe I was just lucky, I don't know. My cats never had any problems with being declawed. I would never declaw a cat that was going to be outside unsupervised, but I feel it worked out best for us to declaw our indoor cats.
Anyway, best of luck solving your problem. There's no easy way to come up with the right solution because everyone would handle it differently.