Besides new reservations, I think these are decent ideas the devs should add.
Biggest thing for me would be a huge customizable lodge
Backfilling more waterfowl and other small game
Having a sell back option on inventory
Improving filtering trophies/deleting trophies
.177 air rifle
Beagles that can run rabbits
Dogs that can tree bears and raccoons
Watercraft that allow you to jump shoot/ spot animals
Better night vision equipment
Adding longer distance to spot and shoot
Different scopes and improve wobble