The new system is being viewed as the End of Stacking, which was initially my fear as well. I've mentioned in a previous post that while
Genie+ was flexible, and allowed for in some cases immediate re-rides, which this won't, I still plan on stacking on some days, mostly for HS.
For instance - our first day I plan to use LLMP for three rides at HS (say, SDD, ToT, and TSMM), plus a LLSP for RotR, all in the afternoon. Then we rope drop MK, with a LLSP for Tron and maybe a VQ for Tron or Tianna. That's potentially SIX rides booked before we leave the room.
Now, I get we can't add any LLs until we tap in to our first one at HS, but there's still three in hand when we park hop after lunch. Under Genie+, assuming a 3PM arrival, how many could we have had? The first at 7AM, and then another at 11, 1PM, and 3? So down maybe one?
The feeling is for some reason that with this system "by the time you get there" for the evening stacking strategy "there won't be any other rides left". Why would that be? Just because people get to book in advance doesn't mean MORE people will be taking spots; in fact, they're should be quite a few less, as it's now a paid service. So I fully expect plenty of options to be available - maybe not SDD, but MMRR was usually there late in the day, as were most of the "second tier" rides.
To me, the downside is no re-rides (we basically marathoned TSMM one after another one night) and a longer booking window - I've heard maybe a 45 minute gap between rides, as opposed to Genie+s, which could have been right after, IIRC.
Of course, much of this remains to be seen ...