#Discourse is really sweet to host and it has a vast plugin community.
discourse.org/plugins

And themes to control what fields to expose
meta.discourse.org/c/theme/61

Fwiw, some of the discourse devs were in the original stack overflow team.

theme

Themes are expansive customizations that change multiple elements of the style of your forum design, and often also include additional front-end features.

^{Discourse Meta}