Machinist are really good in dps and in utility, however, it's too hard to play now.
There is only a few MCH in the game, and there is even less good MCH. Because it's hard to play, and you'll need a DRG with you to be relevant in dps. Also, any death is really punishing.
Right now, if you want to play Support, BRD is perfect for that. NIN too can be a good idea, but is a different way.