Despite having been a frequent flyer for about 20 years, I'm still not completely comfortable with flying. I particularly do not like turbulence (beyond light chop) and rapid changes of altitude. Consequently, I avoid smaller aircraft. I had a particularly unpleasant experience on a commuter (I don't remember the aircraft type) when flying in 80s between Martinique and Guadaloupe. We flew through (not over or around) a thunderstorm. That flight was more than sufficient to keep me away from smaller aircraft.