Not to sound harsh but name on pro who starts at -39 with slow speed! My friend is struggling at the same place you are and has the same idea. After 2 summers of telling him it's the wrong approach I have in. Now he can't even make 32mph -15.
If you want to be able to run -28 your going to need to be able to ski the longer lines correctly. Making six turns and having 3-4 of them correct will lead to shorter lines!!