I checked out your website, and it looks like WordPress should be fine. If anything, since your website seems to be permanent content (except for the news feed and the forum stream), WordPress might have more features than you need; on the other hand, you may start using those features.
If you haven’t, get Apache, PHP, and MySQL running on your own computer so that you can run applications like WordPress without getting on the internet. Then check out https://php.opensourcecms.com/ and look at all the various CMS and blog systems available. Play with the demos and download a dozen or so to try out. Once you get a look at what’s out there, you can better decide what works for you.
As for the CSS, well, I hear ya, but it’s very useful. The HTML is just to lay out the different parts of the page, the fact that it has a header, two columns, etc. and then the CSS determines what the header and the two columns look like. It actually simplifies your work once you get used to it.
For example, your vertical navigation links consist of GIFs images, and there’s a mouseover event that switches the GIF to make it look like a button was pressed. It’s a lot of coding, but that’s how it used to be done. With CSS, however, you make an unordered list (UL) with each navigation link enclosed in LI tags, and then use CSS to give the list the appearance you want, including whether it’s vertical or horizontal.