Every trip has been different! Our trips are to celebrate 5th birthdays, so the priority rides are what that guest of honor is most into. Unfortunately for me, that often means Space is NOT a priority (it is my favorite ride tho!). Most recent trip, our first day in DL we started with the Minnie breakfast at plaza inn, and our first actual ride was GGC, followed by RR and iasw. Not really how I would lay it out for efficiency, but it actually worked out very well for our crew.
I think if I were there alone I'd always start with Space. It is my favorite, and consistently has a low wait time early on, and you avoid the sense of racing that happens towards FL. I've been conditioned to be more ok with longer wait times in FL because of the fun theming to distract you, and that long lines for characters and rides were what my littles wanted to do, so its what we did, but they also were only really into Alice & Dumbo as must-rides. Everything else was an after thought or an absolute no (various combinations of my littles were terrified of SW and Pinocchio, and tea cups line was often more visible and deterred them from being interested, even if it was the same length as other lines).
Our first trip, we arrived in the afternoon and did Railroad followed by Jungle cruise, and both were walk-ons. That trip was full of pixie dust.
