We've changed "Themes" and thus, your "skin" choice no longer applies. If you set your forum to have a dark mode appearance, you need to set it again. Make sure to completely reload the forum after making your changes.
This is the base which i've suggested to modify to make the forum UI of a more accepable quality and style. Do expect to see more changes in the future.
The best part about this new software that I wasnt expecting, was the ability to inject our own CSS/etc code directly into the forum. This should make fixing the site design a trival matter with some decent planning. Please see this image for what a few minutes of messing with the code can do for the site's readability.
While I personally was not happy with the appearance of the forum at first, the potential for something far greater than the old forum certainly exists, so I hope to help FAF achieve that potential.
Also of note, the forum also allows plugins and the like. If you have noticed that a feature you liked is currently missing, please list it here in the hopes that it can be restored with a said plugin.
Thanks.