[@Sylph]

While I am not a mod myself, I have spoken to a few of them on occasion, and while I cannot speak for every situation you have reported someone on for, I can probably tell you why mods seem sort of helpless themselves. 

Mahz doesn't like banning. It will happen from time to time, but it's rare enough IMO. I've heard from former mods it was always a fight to keep someone banned (people who have asked mahz if they could be unbanned have sometimes been granted this request) Because they said they were very sorry or something. Mahz wants to warn rather than outright ban, which becomes a problem when nothing seemingly happens to the user you've reported. 

Their hands may be tied more than you'd think. At least that was my impression when I spoke to them about these kinds of things.

I'm sure the mods warn, probably in PMs- I know they have done things before because I've reported others in the past who have been banned.

As for the rules thing I get that each situation is different and it's not completely necessary to have a ruleset, but I think for the sake of the community it would be nice to get clear rules on behavior etc.

Not sure if that explains everything and I'm not quite sure it is still the same situation with rule enforcement.