No as of the base game, yes if you play with files. You miss out on the 'exponential' stat gain that isn't actually needed, as of now that monsters provide. And you'd probably want to give your Player character a 5 second sex time just so production of units isn't completely borked, as well as starter traits (meta is damage and/or health) since you can't gain traits on the MC overtime.
Nice joke XD.
We don't know for sure , since human female units also have combat animation. If in future version allow human female join defense and raid after get mind break by player character then it's possible to breeding human only tactic to play the game. Though i will consider this as hardcore mode since we only have 1 male unit to breeding.
I would prefer to have more way to play with this game , if only it don't slow down the development or make it too expensive to make.
Are you sure you're palying with the last version of the game ? At some point, I know that a version earlier was causing a mess with saves. Try updating your game to the lastest version (4.0.3 nowadays).
One of the first girls you get is un-soiled by goblins and any new girl captured/born you can have first dibs on. Once your done with them you can just delete them. No NTR