o Less flexible in their use than 35 mm and with a steeper learning curve.
o No exposure automation.
o Limited selection of shutter speeds and aperatures.
o Except for the Mamiya C series lack of interchangeable focal length lenses.
o Problematical with moving subjects.
o Clunky in rapidly changing light conditions having to transfer light meter info to camera.
o Except for the Mamiya C series and some Rolleis the lens resolution is not all that great. Avoid those cameras with 3 element taking lenses.
o Film loading is slower than 35 mm.
o Parallax problems.
o Limited choice of films compared to 35 mm.
o Square format.
o More prone to film transport problems.
o Harder to focus particularly in low light.
o Reversed image in view finder takes a bit of practice.
o Leaf shitters need servicing more often.
o Overall somewhat less robust in design than 35 mm cameras. Too many points where dust can enter.
o TLRs are fine in the studio and for scenic aand still photography.
o Larger negative.
o Less likely to be noticed as a camera in this digital age.
o Easier to use for those wearing glasses.
As I recommended to the OP, try one of these cameras first to see it they fit your needs.