Why is that an issue? Fighters have very limited ammo, light armor and limited fuel. Bombers have heavier armor and are bristling with defensive weapons and fly in tight formation. Shooting down bombers isn't a milk run. Why should one squadron of fighters be able to take down many times their number in bombers. They never were able to historically. Shooting down waves of bombers took many squadrons of fighters and even then lots of bombers tended to survive to make their attack runs. Or in naval aviation, fighters had a hard time shooting down torpedo bombers until they were stuck making an attack run. Bombers aren't sitting ducks and one squadron of fighters probably shouldn't be able to take that many of them down.
In WWII, the allies tried several methods of escorting bomber waves. Including fighters in the wave worked sligjtly better than no escort at all, but once the fighters reached the bombers it was very difficult to keep them from making attack runs and we lost figjter escorts to friendly fire from the bombers defensive weapons. They eventually started sending up deep escorts to clear the air of enemy fighters before the bombers got there, which was the most reliable way of keeping bombers alive. The current system of sending individual fighters to clear the way and deal with CAP before moving bombers in reflects this strategy very well. I see no need to change it.
As for attrition, its realistic but it would be a real pain determining which squadrons were dead and which just went back to rearm. And keeping track of it would be no fun either.