This game books pretty cool, but I think I'm in one too many, already (esp.as large alliances generate a lot of work)

One comment; you might want to think about the balance effect of UlM. It could easily turn into a magic item factory fed by all the gems five allies can send it. Protected by its allies, and allowed to concentrate on alchemy and forging exclusively Ulm could become very gross, and massively boost the side that gets it. I don't think any of tho other races would synergise with alliance play in quite the same way.

Mark