Do you honestly within your heart of hearts believe that SSE or Living with the Land have a higher GSAT than Frozen, Ratatouille, Soarin, Test Track, or what GotG is likely to have (especially with it being the first coaster in the park)? I like SSE and Living with the Land quite a bit, but I just doubt they can compete with IP driven rides, more intense rides, or something like Soarin which is fun for virtually all ages.
When Disney announced they were getting rid of UoE and GMR, they did it in part because part are hard to find, but also because BOTH RIDES were reported to have extremely low GSATs at the time of closure and the years leading up. There was actually a GotG ride proposed to replace GMR a few years before MMRR was announced.
And honestly, I really believe about 6 minutes is about the max amount of time a ride should last unless you something great to offer me and it's not just a waste of my time like UoE was. Your position seems to be "Longer = better" which just isn't true. A good ride engages the guests in some sort of stimulating way or by pulling off something that leaves them with a true "wow!" moment.
Pirates at DL I certainly enjoy more than MK's, but only because MK's is so mediocre. Tbh, I almost wish MK's pirates would just get replaced by Battle for the Sunken Treasure and to combat your point about ride times, both MK's Pirates and Shanghai's are around 8.5 minutes. Shanghai just has action baked in with the ride.
Back on track to GotG...