So first off, I'll just say the upgrade to the UCP format for this wiki, isn't great. Sure, everything works on technical level, but usability and ease of editing have made things quite difficult. Won't list everything I have issues with, mostly because I don't currently remember a lot of the minor gripes, and I don't want this post to become one long complaint, but one glaring issue I've come across, is the inability to edit tables. You have to do any real editing through the source format, which is how I did a moderate amount of editing to begin with, but now I'll need to work in Source Mode even more, which makes things more difficult. Also, UCP doesn't seem to be desktop editor friendly. They focused primarily on mobile editing, which is fair, since apparently a majority of views and edits come from mobile. But when you need to make major changes or even start up a new wiki, I'm probably not in the minority when saying that I'm pretty sure most of those are done on a desktop.
As I mentioned earlier, I most likely won't switch Wiki platforms, for two reasons. One is, it's going to be one hugely major pain to transfer over 1,000 pages to a new site. Secondly, there isn't many options to move to. To begin with. Gamepedia is also switching to this same UCP format, since they're also owned by Fandom, Mediawiki requires a lot of ground work, plus your own hosting site, which I'm not going to get involved with. Hopefully with time, functionality will improve, but we'll see.