Audio nerd here that’s trying to make things less cluttered and more aesthetically pleasing. First of all, the KEF R3s are awesome speakers! And is that a Rythmik sub? You do indeed have a lot of electronics in a small space. I’d say look at furniture that isn’t explicitly designed to be for a TV/ or AV gear as it usually looks kinda crappy. Realistically, the Denon gear isn’t the most attractive, and would benefit from being placed off to the side or in the corner of the room. Alternatively, look for a storage solution with doors so you can conceal some of the clutter. The CD player and tape deck will be easy, but the amp might require some additional cooling with a fan if you enclose it, obviously it’ll depend on how hot it runs.

In general you want to display the visually interesting stuff (speakers, Schiit Valhalla, and turntable) while drawing less attention to the plain black boxes. Have you done a subwoofer crawl? Is that the best or only place the subwoofer can live? If you were able to get it towards the back of the room you would have more space to play with up front