Few days ago I was looking at my Oxwall site and noticed that alowing users to customize their pages( profile/ created group) wich is an good feature in principle could lead to a messy community as the user can add as much custom html/css boxes as he wants and in each whatever he wants(flash, scripts, tons of adverts ...)

I posted some sort of suggestion and didn't do my best but, if you think adding permisions/limiting what users can add when customizing their pages, vote for it.