It's been a while since anyone updated the wiki. I've personally threw a bunch of monster namespaces in each 'Monster by Level' section, hopefully everything I have in data from my account (~38%). The goal that I'm wishing for is for people to contribute to those namespaces (including myself), completing one section to another.
I think Level 30-39 needs to be finished, so that should be done first. Then we'll take care of 40-49, and so on. And if I apparently missed a monster, please make one and remember to add it into the corresponding section.