This class was never really good... if you have the money to fund it you can be decent but a brm can never actually compare to a bp.

get the lvl 30 set (Talin/Sayram) to start with, if u can afford one with great awakes, or just make a vagrant set with some epic awakes on it. High % Crit / adoch / aspeed / str / dex
for build you need to reach attack speed cap, so you will need to add dex in build most likely, haste cap is higher for RM's than it is for BP's I don't remember what it's at since I quit the game lol... but i believe it was at 93 or so dex (you should really look that up). When ur aspeed is maxed out dw about it anymore
For knuckle go with GK then HK then LGG. Unless you have another knuck with godly awaken, however LGG would be your best choice for dmg.