This video on doubles pickleball strategy gives tips and strategies for returning the serve. It discusses reducing unforced errors, leaving a margin for error, and getting fully forward to the line on time.
Joe Baker is the most intelligent, articulate, and rational coach. Everything he says makes so much sense. My only addition to this video is that playing indoors you can aim for a bit closer to the lines but when playing outdoors you need more margin for error and random factors, especially the wind.
Good advice, however note that when the skill level assessment says to return the ball to the back half of the court, they are talking about the full court from the net to the baseline, so 11 ft. from the net or 4 ft. from the NVZ line. Your analysis used a percentage from the NVZ line to the baseline. Half of that is 14.5 ft. from the net or 7.5 from the NVZ.