I dont see anything on default phpbb for post count limiting. There are ways of restricting what images are posted. Such as the size being a 10px by 10px, they would post, and realize no one can read it, as well as the trouble of initially getting that size anyways, then copy and paste it and remove the image (hopefully). I mean how many times do we need to use images anyways? We could just default image back to links such as imgur.com
I know they have mods for post count limiting for restricting certain forums. There might be one for image posting. But then again we need shell access. It would be nice if the admin was a constant user of the forum. IT would be nice if Taos/jkbbwr forfeited his admin power to stranac or micseydel or both.
regarding another issue of new users deleting their posts. I see a "limit deleting time" option for new posts under General -> Post Settings. Which is currently set to 1440 minutes. 0 is disable, so 1 would give them 1 minute to delete their post, wouldnt it? That might fix our problem of homework helpers deleting their initial post after getting help.