As others have said, if you get it, then you can modify, but Slinky goes quickly.
We have had so many bad days at HS, that we now tend to skip it, or only go for a few hours. Getting into the park always seems to be very slow, like we lost half an hour - all of Early entry- just getting tapped into the park the last 3 visits.
On my most recent visit, we had a gap in our G+ bookings, so we got in line for MMRR. It was supposed to be a 30min wait, but ended up being well over an hour, because they just were not letting any standby guests onto the ride. The extra delay mucked up the rest of our time at HS. And that was just the most recent disaster day at HS.
Every time we've gone to HS since G+ started, the experience has been frustrating like that. If any of the rides go down, the park just grinds to a standstill.
HS badly needs more attractions and new shows. They quickly need to put something in the Little Mermaid theater.