Just had a chance to play a 4 player game with these.
Uhh... they are not really balanced at all for slightly large decks. The River + Traders and Builders + Inns and Cathedrals + The Maze + the original monasteries because why not? + a second pack of 8 city tiles I bought and this thing is just broken. If you never draw one, you simply cannot win when people are getting 25+ points per Japanese Temple on huge, congested boards on long streaks of tiles, due to the River.
There's is absolutely no reason to take this as an Monastery. I can't think of any situation where you'd want to give up 25+ points for a potential 9 points, unless you were down to just your Phantom or something and didn't want to bog it down all game.
So everything you say applies to the German monasteries or Belgian monasteries or presumably Elbonian High Places.
First;ly it is harder with 4 players. With 2 you are likely to at least get say 2 of them. Also the more they invest into long term stuff the more you can invest into farms and cities. Also it may be possible to block the growth of monasteries influence - especially effective if they are on the same line. I'm not convinced it's unbalanced.
Also there is the choice of expansions. You had the labyrinth, right? That definitely sucks meeples out of the game. When the labyrinth comes up again it might be possible to trap the opponents meeples in the labyrinth rather compete. Sure you still losie out on points. But committing a meeple for the whole game is its own cost.
Also there are other expansions that balance things out a little. Towers allow you to capture an abbot. Very nice if done to a long-time abbot. Fliers enable you to get in on the act after the fact.
Also the original rules say the special monasteries should displace the normal ones but we have never played that.
Edit: It should have been "The Most Sacred Shrines of Elbonia that look exactly like Mens' Restrooms Expansion Including Statue to the Monkey God Oobanoobah". For reference see
http://dilbert.com/strip/2012-06-18 and
http://dilbert.com/strip/2010-10-17