Things I've been looking for on the Wiki but not finding lately (most of which I've asked on the forum):
Tips on class challenges, as mentioned. Suggested preps or race when possible, basic stuff. Minimal spoilers.
Effects of Patches the Teddy.
Any strategies regarding unlocking/kingdom building. Some people might run to pile up gold early (by avoiding hitting a diverse range of bosses), or to unlock as many classes or races, religions ASAP, or there might be what vets consider an optimal order which is a combination of several or all of these. Stuff like that.
A place that references advanced tips; regen fighting, punchomancers, acidcasters, other various goodies.http://monster-wiki.com/
<-- that's a wiki for a FB game that has had literally everything I've wanted to look up. I'm sure there's probably way more people there working on it, but pretty impressive. Sadly, I know next to nothing about wiki-editing and I'm only moderate at DD. :/