Depends what you’re after, if you want some XC style stuff, then the blue/red will give you that, if you want to do DH runs then get up the push up path and do that stuff, at the beginning of Ski Run you have the tabletops you can practice on, GBU has the first section you can play on and so on, or you can do full runs.
You could also mix and match, first climb of the red, up until that steep bit to the fireroad, then head along but go past the red and head towards launchpad and do that.
I’ve done it a few times, you can mess about at the top half for ages, or head over to Y2K/Elephant Man which are good fun as well.