If you have time to watch 110 TNG episodes, surely you have time to watch all 178 and decide for yourself . . .
ETA: If someone *needed* a really short list for some reason, I have a list of 20-odd episodes that follow the progression of the most interesting ideas
TO ME in TNG (Data, Q, the Borg, time travel). But it's really best for people to watch it all and decide on their own.
I do have to ask, how is Menage A Troi at all helpful in understanding Star Trek? It was boring and pretty much pointless, as I recall.