Thanks again to asezawesome for thisn suggestion.

Enemy of goodness (truth, beauty)

Well no one wants to oppose good do they?  Because good is well…good.  As is truth and beauty!

No one really wants to be poo do they?  It’s insulting because poo is yucky, and no one really wants to be yucky.

Shithead, shitbreak, shitface, wipe your mouth you are dribbling shit.  Be careful to not use this to link to male homosexuality, in which case, it is a homophobic slur, and you don’t want to be a shit, so don’t do that.

Arse/ass, and all it’s derivatives - arsehat, arsehole, arsewipe.  Must be careful to not link these insults to sexual activity, but generally they are saying someone is a producer of waste product.

If you have any suggestions, please submit!

Douche and it’s variants - douchecanoe, douchebag.  -nozzle, -guzzler, -rocket, -humper, -canoe) (With thank to asezawesome_ for the variants)

Okay - doesn’t speifcially reference a minority group or marginalised group.  Insulting because douches are useless, uneccessary, and additionally, actually harmful to vulvas and vaginas (and so potentially, their owners!)