I wish I could help with the HTML but that is not something I know. Keeping in mind people come here for custom maps I’d say focus on that as much as possible. I’d keep the Quake Injector if the tool is going to be modernized at some point. I’d lose the Guide links. Maybe one link to “New to Quake?” that leads to Guides on a sub-page. Shorten all feeds to a smaller number like 3 or 5. Less clutter overall this way. As a modder I’ve always appreciated the links directly below the thumbnails for wads and maps etc. but I am not sure you need all those if the focus is playing maps. Maybe it’s time to introduce a side bar for all those options?
I’ll look at this more closely when I can and come up with some more concrete suggestions.
I think the main question is what is the main purpose of Quaddicted? And use that as a guideline. IMO it’s finding maps to play - for most visitors anyway.