I agree that ordinary people doing ordinary things is enjoyable on a soap opera level yet can also easily become problematic. I guess that's why DS9 featured not so ordinary people (and worked because of that?) and why Lower Decks ended with a not so ordinary, heroic sacrifice.
Talking about ordinary people, I think it was McCoy bringing common sense and the voice of an ordinary guy into the discussion which made TOS work so well character-wise.
TNG either presented an ideal, technocrats who, unlike real-world technocrats, are competent and make difficult decisions, or a more TOS-ish situation in which ironically the robot asks naive questions or acts in the most human way (Pen Pals) and thus makes us question the technocratic consensus.
It is a complicated issue and I think my initial point was wrong, good stories can very well flow out of well-written and -played characters.
About the number of episodes, I agree that more than 20 40-45 min episodes per year is too much and that around 10-15 would be better for the "supply side" reasons you mentioned but also to avoid "demand side" problems like oversaturation.