I haven't heard any of these myself, so I don't put too much weight into my input here, but I'll share my thoughts.
Clearaudio is always highly reviewed, but I have NEVER met anyone who actually owns one. To me, that says something. Whenever people are shopping within their price points, they always go a different direction. I don't know the reason, but that's always stood out to me. I'd still love to hear one, but that would be enough to prevent me from ordering blind. They do have the most arm options though, so I do think that's a pretty solid advantage from their lines.
For Luxman, their stuff is beautiful and reviews are positive from both critics and actual owners. I also think the knife edge bearings are interesting and they seem like a good medium between a classic gimbal and a unipivot. The option of various armboards is also very cool. And in the removable head shell, you're looking at a ton of great flexibility. I do prefer the look of the Centennial, but I think the technical upgrades of the 191 are enough that I would heavily prefer that if I had the option. 191 just feels like a table that will not limit you in the future, especially with the armboards.
Now the Rega, while a totally different design, it has some awesome advantages. One is being dead simple and easy to maintain, especially if you stick with Rega cartridges. In my mind, this is by for the most set and forget of the bunch. I have also seen Rega arms on more non-Rega tables than most other brands. That's a huge endorsement to their arm designs, and that's worth considering.
For me, I'd go Luxman 191 all day. To me, it feels the most future proof. But like so many great things in hifi, I think you've got a good list with no wrong answers. Don't be afraid to just lean into he one that speaks to you most.

