^ I didn't care for Pulaski either. It was in some respects an interesting tie-in, bringing a TOS guest actor into the TNG cast. But her personality just didn't work well as a ship's doctor. I didn't like her voice and her mannerisms for that role. Just didn't feel right.
And apparently Maurice Hurley, one of the head writers, had some friction with McFadden. He was instrumental in having her fired. Then he left at the end of the season, whereby Berman decided they should bring back McFadden (Pulaski wasn't working out). It was likely more due to the complications of introducing a 3rd doctor, and there was a nice plausible "fitment" to bring back McFadden, given Dr. Crusher being Wesley Crusher's mom. I think they were right to do it... as ultimately it did work. But I never liked any of the episodes where McFadden was the lead. Like in Sub Rosa.According to comments on the Season 2 Blu Ray, Gates McFadden was very vocal about the tendency of the scripts to run sexist in the first season, which created tension between her and the writers and producers. Patrick Stewart, on at least one occasion, stood up for her and added his voice to the complain leading a script to be largely changed.