i like the way you are developing this project, the interface developments make sense and i’m sure you’ll dial in the aesthetics further when you have more of the the users and their needs figured out.
i like the design of the bezeld cylinder body in your first picture. i wonder if you used a knurled or textured pattern on the beveled surface or on the vertical surface below it as a grip and aesthetic feature of the design ? how about having the 1-12 clock numbers embossed/debossed on that beveled surface ? in that way, when you rotate the bezel to reschedule something, it would ratchet around to the desired schedule position and then spring home to the original clock position ?
the persona suggestions are good, i would back them up with some visual storyboards, showing more about the consumers lifestyles through activities,influences, brand loyalties etc. i would suggest also considering a much older user, blending some classic watch styling into your modern interface design, keeping them in touch with the old and the new. it could have a dome shaped screen, maybe the body has a classic winder as you have suggested in the sketch that serves as some sort of navigation or control. i don’t mean a total steampunk job, just some cues and influences of it might be worth considering…