My wish is for the game to remember what each soldier was equipped with in their last mission, and to try to load them with that same configuration for the next one. As a bonus, on returning to base from a mission, the game could warn you if the base doesn't have enough (ammo) stock to re-equip for next time.
I also like the other ideas mentioned so far
I think that's what XcomUtil tried to do, but it had a lot of bugs when equipment changed or you lost soldiers.
My idea for a pre-equip screen to prevent these kind of issues is that you could individually equip your soldiers however you wanted, but it wouldn't be "real" equipment, more like a template. So the game would just fill out the templates with real equipment when you went out on missions, and would never lose them whenever your soldiers or equipment changed, it'd just warn you if you suddenly didn't have enough equipment to fill out the templates.
Personally I never bothered to have stats-specific equipment and just had everyone carry the same because I'm lazy
but some ability to save templates shouldn't be too hard.