Thanks for putting in the work solops!
As far as maps goes, my thoughts are:
1. I would make sure you know how to upload it into Llamaserver before putting a lot of work into it. I know W8taminute and I in our 1v1 games found that a stumbling block.
2. If we are up to 6 players, I believe the other map that ships with the game works for that number. (Peliwyr, I think). Already comes with caves and generally balanced start positions. Easier than
3. I would prefer to keep provinces per player in the 15-20 range. I prefer slightly smaller and faster games that gets into fighting other players, as opposed to fighting independents for a long period of time. 15-20 also ensures that a single bad expansion won't screw you, as the difference between 12 and 15 provinces is not as big as the difference between 7 and 10. At the same time, it keeps things moving fast.