It seems to me that a lot of members' problems with this subreddit is that there are things that have nothing to do with campaigning for men's rights and have more to do with venting or providing jokes against feminist oppression. Obviously, this subreddit does have plenty of good posts directly related to men's rights, but those are often interspersed with pure venting. Why not have a subreddit both created and linked in the side bar to direct such traffic that way? I say this as someone who both is interested in men's rights and as someone who feels the need to occasionally vent, but doesn't want to derail the subreddit.

EDIT: I forgot to add that /r/mensrights doesn't have to directly support such a subreddit, merely direct venting traffic in its direction to keep itself more focused.