Nope, complete opposite. With regards to artistic talent, the scale is so heavily weighted towards the absolute flakes that it's not funny. Orson Wells once question if an emotionally healthy man COULD be a great actor. I think Orson was pretty much spot on.
Self-indulgent, inconsistent, neurotic types tend to reach higher rungs on the creative scale than people with character. My guess, and it's purely a guess, is that stable people aren't seeking escape from their tortured lives 24/7 in their imaginations. Artists of all stripes are constantly retreating into their imaginations seeking escape, and that fuels the genius.
People of great character are so often multi-talented, like
Reagan & Condi Rice, don't you think?
People who confuse talent with character seem to be the narcissistic
types you and Wells describe.
Some exceptions I admire are
Mel Gibson, Jimmy Stewart, Robert Duvall, Jean Stapleton, Ginger Rogers and many other principled stars and leaders.