Your Mileage May Vary. Did Roddenberry leaving the show hurt it? I'm not as certain of that as you are. By the time he leaves over the disagreement over the timeslot, I'm sure that some of the third season scripts were already being written. Add to that the fact he was already trying to sell other projects (Assignment: Earth) and that the second season didn't necessarily end on a critical high note. Season 3 may have been just as much rubbish with Roddenberry at the helm. YMMV.