Brucher, are you prepared to open Pandora’s box with just one cattleya?
I grow about 70 on various south or east facing windowsills and nearly all do great.
I don’t have a single Walker as I’ve been told they love high humidity and that is one thing I cannot offer, but others may disagree.
I grow pretty much only large flowered unifoliates species. The big three are labiata ( autumn flowers) trianae ( winter flowers) and mossiae ( spring flowers), so when do you want yours to flower?
Then there are summer flowering species like warscewiczii, dowiana, rex.
Within each species there are myriad colour forms, alba, semi alba, coerulea, rubra, aquinii etc etc it’s just a case of choosing.
If you are after special forms then cattleyas are the ones to collect. There are hundreds with prices for pockets of all depths.
The fischers’s at Orchids Limited have a nice selection of high end cattleyas on their web site if you want to start to investigate but plenty of others in the US offer divisions or mericlones, e.g. Hausermanns.
A really good place to start is Chadwic’s book ‘ the classic cattleyas’ which is just going into its second edition this Christmas. It’s on their web site. If not, look at their web pages on the individual species.