FreeTrade: are you still updating this?
How you consider the
MMC value going down? I've mined for months them because my considerations about that coin was the very same as yours

Only one negative point you've not listed: the pools are not at all distributed.
1GH.com and
mmcpool.com represent mote than
95% hashpower between pools. I don't believe there are many solo miners so this is a problem now. This is due to the fact, I believe, that
the only GPU miner is not open source, it's compiled and owned by 1GH.com. This must be solved for the future of the coin.
My only fear is that MMC could go in oblivion like many other alt coin

The GPU miner is really not a factor since GPU mining is very bad with this coin (it was good for about a week or two until yvg1900 released his Yam Miner for MMC which eliminated this advantage).
I think it is safe to say that MMC is the most (or one of very few) GPU resistant coin existing today.
As for the pools - The coin's CNO is working on a (already in beta) p2pool to solve this issue...
This should hopefully move many people to use the official pool with far lower fees (1%) and will create a better hash power distribution.