Am not sure what could be done. The pm wave as I understand it runs from 11:56 - 1:56. So how are you going to deny those with 1:32, 1:40, 1:48, 1:56 t-times the chance to play if only for 9 holes (allowed between 1:30 - 2:00) and I agree that some are new or slower than more experienced players. They could opt for and often do play 18 and some are not slow or new players this time of year. The issue as I see it and has happened to me is that play for 9 is allowed about 2 hours. When we play the front 9 in say 1:45 with an 11:56 t-time we will be turning to the back 9 about 1:45 pm. We then have to wait for the rest of the pm wave (since it goes to 1:56). Courses in their defense are quite busy compared to summer time when there has been little or no wait at the turns. Courses with straight t-times don't have this problem, unless you are behind a slower group for 18 holes. Imho that's what I have experienced and discovered from looking into our t-time system.
One way around the issue is to play in the am wave where there is no 9 hole play to meet at the turn