Sorry if this has been discussed before, but I have some ideas on weekend Routes 936, 937 and 939. Comments welcome!
Routes 936 and 937
While this would increase walking distance for some passengers, I think these services should run direct via Antill Street through Dickson and not detour around the back along Dickson Place. The whole diversion only services the one stop on Cowper Street which isn't very far from the stops on Antill just west of Cowper. I think this would be particularly beneficial on the 937, which services the Antill stop, loops around the back and then goes past the same Antill stop a second time. After all, the 39 on weekdays runs via Antill St direct.
Route 939
Fairly simple idea for this one, and probably one which has come up before. Reverse the loop through Watson so it goes the same way as the 39 (or, I guess, you could reverse the 39...whichever is best). In my opinion, the services should go the same way, so it's easier for people to understand. Last time I was on a 939, someone was waiting on the other side of the road, but luckily the driver saw them and was able to get their attention.