Well, I used film all my life, and I can say the thought of going back to 4x5 is horrendous!
We used it almost exclusively in the industrial unit, sometimes going larger, and also a little bit in my first commercial job, but if you ask my opinion, which no one did, I'd say anyone thinking of 'starting' with 8x10 would be better starting with a visit to their local mental heath centre. Forget it.
If you really feel you want film, go no larger than one of the 120 roll formats; it'll give you anything you realistically imagine you can do. Should you someday feel the hand of the good goddess Gallerie on your shoulder (or in your pants) then yes, if she promises more for 8x10, rent and try her out...
You can be as deliberate, slow and/or anal as you like with any camera.