Its not about the camera or back of course, it's about what you do with it, what helps me tell my story and solves certain problems I have is the camera I use.
Could I shoot everything with a DSLR?
Yeah of course, but the credo60 I use has a totally different look and feel to the end result, when I shoot film it's the same thing. I will sometimes shoot Minolta, petri, zeiss lenses for their look and feel they give to the shot not because there is one picapixel difference in quality. When you print for publication there is hardly any difference in perceived sharpness, however the look, bokeh, color etc. all stay in tact. For example we have an A2 print from a FujiFilm 400F pro film (35mm) hanging in the studio scanned with an Epson v700 even when looking really close the print is razor sharp and there is hardly any noise, when looking at the screen on 100% it's noisy and soft. If you let the screen guide you you will actually aways pay too much
In the end it boils down to a workflow, (medium format is a beast when shooting tethered, always when I shoot a DSLR I'm slowed down because I will hit a buffer, with medium format there simply isn't a buffer), look and feel of the final image and not unimportant in some cases the use of leaf shutter lenses and the control of DOF when shooting a larger sensor.
That a leaf aptus would be more with the manufacturer than on the camera is weird, I don't know what you do with it, but we travelled a lot with an aptus22 and later aptus7II and I never ever got a problem with the back, I always found the leafs to be build like a tank. But maybe you have been unlucky ?