My camera arsenal ranges from Minox to 4x5 and its accumulation spans fifty+ years. In the last few years, being retired, I have gravitated to medium format out of a sort of "Goldilocks Theory" -- not too big, not too small, ju-u-ust right. That said, I now have a assortment of MF gear to choose from. For what I consider "really serious" work, I go to my Bronica SQ-A. When portability is an issue, I have a 6x6 (Perkeo II) and a 6 x 9 (Ercona II) folder. For reasons maybe no more than just plain GAS, I recently acquired a Yashica 124G which has been my walk-around gear on some recent trips.
I've done some pinhole work with my old B&J 4x5 in recent years, but I don't have a good enlarger, or even a good space for 4x5, and the film is expensive. (Much of what I used to shoot on 35mm is now done with "alternate technology" which means the pictures are free -- after the initial 3 or 4 grand of capital outlay! )