Some issues i think reddit has is that they haven't been great about helping their helpers. I remember toolbox being the only way to moderate properly. It not actually being a tool by reddit itself and a massive resource hog and hampered by the size of the wiki for big subs.

Also reddit not curating the moderatorship of it's big subs unless there's controversy. Making it so the top mod can basically take over, disappear, etc. Basically the tiered nature of mods is an issue imo.