Some of the later hybrids used varistors in the high voltage regulator circuit that liked to break in half. I don't know how rare they are but these sets loved em. Also, replace the red rectangular rectifier on the convergence board if it hasn't been changed. It'll burn up and kill one of the blue convergence controls. Check horizontal current or it'll devour damper tubes.
I don't remember these eating flybacks or yokes unless something (horizontal centering control) burned up on the flyback board and caused it. If the set has a focus divider, mount it away from the chassis to prevent it from trying to break down and arc to the chassis.
Tuner RF amp tubes were prone to failure.
An RF modulator and a video stabilizer is the best bet for DVD and VCR inputs. Otherwise, those aggravating lines (dvd) and flag-waving (vcr) can occur.
I can't think of too much more. These were reliable sets
The space command can be a bit of a challange, but that is another post (coming later)
