Thanks for playing! Sorry I missed this comment for a couple days. I wanted to get guard allies in this update, but there's a lot of back-office stuff with how I've been messing with the game engine as a primarily single-character game that I have to work out how to undo to add allies, so not yet.
Generally speaking there's no benefit to having skills over level 50 right now, but there will be more blacksmithing and other unlocks for higher level skills in the future.
For the mine bug, can you give me a little more information? I haven't heard that one before and I'm not seeing anything obvious that would cause issues there.