Sadly MRC/BTC not existed, for me MUCH harder to calculate with MRC/LTC lol
Its easy to calculate in Satoshi's 1, 10, 100, 1000 Satoshies is Ok. And i also dont like LTC also (with ASICS, hackers steals selling dumps etc)..
Yes, best should be if there is mBTC market when price is under satoshi.
LTC market is made only because it makes more trades. BTC vs mBTC no need to exchange