Let me poop in the nest by saying that I have only one regret regarding MF and that is buying a Hasselblad 503CW with the 80mm f2.8 Planar.
Why?
Can't nail focus with that one, I even changed out the focus-screen to a Acumatte-D (without an annoying split-screen), it really is hit and miss.
Also, the lenses have such long throws that it takes a fair amount of turning just to get them into the ballpark, it doesn't help that the focus on the lenses are very hard to turn as well.
The 50mm (can't remember the name) CF T* something is very hard to work with, as it has inherent barrel-distortion, quite difficult to get a straight -anything- with it.
So, I regret that indeed. (still have it, rarely use it).
Still have a bunch of 35mm that I shoot regularly with,from zorki's, to Leica's to the Canon 1v.
And I have a bunch of (other) MF cameras; Rolleiflex Automat MX-EVS, Rolleiflex 2.8F, Mamiya RZ 67 pro II, Bessa II 6*9 folder and a Yashicaflex.....and a Moskva V (with a crooked field of focus, so it's for display only).
I did look at 6*4.5, but, apart from convenience of the size of the cameras and the increased quality in the bigger negative, compared to 35mm, it's not that interesting for me. My Automat is tiny and delivers 6*6 so...
I would never go back to anything, I shoot multi-format (apart from LF), to each it's purpose.