Interesting question. Am sure will be different for everyone given each of our personal likes/dislikes. For me, spending more that $1500 for any OTA is a major decision and have only done that twice in my observing life. As a general rule I will commit more funds towards any refractive OTA than any Catadioptric OTA, and will commit more funds towards any Catadioptric OTA than I would towards any Newtonian.
At my age (58), $5K is my max, period -- and it would have to be a very special scope. Spent $3K total on my APM 152ED -- youch! But, it's been worth every penny for an old visual observer.
Like you, I'd put more $$$$ towards a refractor than any other design; but, I'd spend good money on a high quality Reflector (including Classical Cassegrain) before a CAT. I got all of my reflectors at much -- Much! -- less than they are worth visually. Absolute bargains.