Concerning Fief defence: If there atttacked have them surrender if they have little troops stationed (as in that bare minimum default), or maybe if the ratio os to high (1v4 odds)

General idea is, as you mentioned, "it’s always a lower number than a minimum enemies attack with, making it impossible to successfully defend a fief", so what's the point of making it a battle if it's just going to be a slaugterfest? If they have no odds already?

Really what I'm saying is if they don't have troops stationed there before the attacking army arrives, why not have it declared a victory, after all it only had enough people garrisoned to ward off bandits, much less a organized force. Or maybe if that ratio is too drastic (lets say they put 50 extra troops and a full sized army attacked, outnumbered 3v1, they surrender.

All in all, if there is not a ample defense force there, just have them take it bloodless and have maybe a "short" version of raid where they maybe fight off a few bots (guards, not players since there army anyway) and cap O and scatter around some treasure chests for players to find or something. maybe better yet have a cut scene with the attacking "commanders" beside each other and raising there flag on some tower looking all heroic... idk.....

Regardless, please have the possibility of surrender somewhere.....