I have had plenty of artists and writers who have graduated from Stop Smoking Clinics. I can't recall once ever having one leave their professional field because they quit smoking. Most of them realized relatively quickly that they became more productive after theu had quit smoking.
The bottom line is that all people who are smokers must recognize that all of the things that they do as a smoker, they can still do as ex-smokers. They have to teach themselves how to do these things but the way they do this is just to continue living their lives and doing their daily activities after they quit.
Below are a few links to articles that hopefully will help address some of the concerns you have raised. I am not sure if any writers or artists read here at the site, but if they do hopefully they will add a little more personal insights. It is just that no group of people should feel that because of their profession that they are somehow handicapped at quitting smoking. Any person in any profession can quit smoking and stay free if they simply make and stick to a personal commitment to never take another puff.
Joel