Wow, nice. I have a 452 Ultra Lux (Super Exclusive) that’s remarkably accurate. It's one of my favorite guns.
I didn’t notice any 455’s in your collection. The 455 is a new rimfire line with interchangeable barrels. They haven’t finished releasing all of the new 455 models yet, so that could keep you busy for a while. I don’t know how specific you want to get but many of their rimfires are available in .17HMR and .22WMR also.
I also didn’t see a 451. It’s also a bolt-action rimfire. I understand this was one of the last guns Brno built, and not up to their usual standards, but it’s still collectable, right?