Unlike a digital frame, a film frame costs money and resources and cannot be instantly reviewed. In the end, you want the camera that you can handle most reliably without needing to double check results, wasting the least frames. Reconsider using any feature great at "perfectly nailing or perfectly ruining the picture" (spot metering, unless you are very secure in its usage, comes to mind).
Some automation features (autofocus, matrix metering, TTL flash) that some would consider optional in a digital environment can help you waste less frames.
Features (like fully-automatic, subject-specific modes, "chip card" systems) that were aimed at snapshooters and minimizing required skill at the cost of available control will not likely be interesting for you, and could actually create wasted frames if accidentally activated.
Looking into how viewfinder coverage plays into the film workflow you want will potentially help your composition - you might want 100% coverage in a film SLR if you are scanning film strips straight, 95%-ish if you are projecting framed slides, and whatever works best with the printing workflow you use if printing (or ordering prints) from negatives.
Precision (lens mount, focusing screen and film gate alignment, shutter and meter accuracy, autofocus accuracy if using autofocus) and reliability in the camera build certainly will help. Otherwise, the camera body does not matter that much for image quality (excepting some rare innovations like the vacuum-assisted pressure plate in some Contax RTS models) - it is usability and ultimately style you are looking for.
Mind that a camera designed for informed-manual operation (eg a Minolta SRT-303) will be optimized for that handling mode ... and with some practice, MUCH quicker to handle than eg the manual modes on an autofocus-oriented SLR.