The trick is to find the gross women (protip: search tumblr for the names of main characters until you find something unhinged in its horniness. Or search Marine Meat Monday.)

/Grimdank is pretty ok, and most of the fandom for Rogue Trader is a blast.

Be sure to block/mute/whatever anyone who focuses on the Custodes too much. (Not that Custodes are bad, just that the dust up over Custodes made plain the assholes)

Youtubers I recommend are Krakduck and Isander & Koda.

Avoid facebook and twitter.