Just back last night from a 5-day trip, I used the new system every day and prepared the best I could by using Ear Scouts and Mammoth Club YouTube videos - to understand what I'm going to say below, I recommend you watch them, because I am slammed at work this week and will not be able to answer lots of Qs. I am not going to talk about SPLL here, though we did those, as well; they were prebooked, so I didn’t look for drops or new times.
I had a pretty relaxed first day (I did AK in the morning and only fiddle-faddled a SDD and MMRR for later in the day, just before DHS after hours, which I was attending), but for the other 4 days, I rode literally everything I wanted to ride every single day, including Tiana (every day, and I had only prebooked 2 days), Remy (every day I was in Epcot, including 2 days I had not prebooked), and SDD (2 days, neither prebooked), and at convenient times, without breaks of more than 10 min in between. The only day we arrived before resort guest EE was Saturday, to rope drop Frozen at my niece's request. Perhaps that day was the best example - we had planned Epcot with a hop to MK, and did the following starting at park entry: Living with the Land ("unlock" ride at 9 am), followed by: Remy, Imagination, Soarin', Frozen, relaxing early lunch in A/C, resort for 45 min, PP, Tiana, Pooh, BTMRR, Pirates.
In short, I loved G+, despised FP+, and was very reticent about this new system. I was wrong. The ability to hold three attractions AND modify them is huge. After using it intensely for 5 days, I like it better, but it does take understanding, effort, a willingness to at least enter a park at/around opening every day to badge into a ride immediately, and spend some time - though less than you are likely thinking - modifying ("fiddle-faddling"). It will deliver less for people who do not want to get up early, or at least get into a park at opening with an early MPLL booked (any one will do), preferably the earliest time available even if that feels silly; it will also deliver less for those who do not want to spend time modifying (I do understand that this is something some people do not want to do!). Below are a list of "hacks" or potential ones that worked for me.
1) Current "maybe" - chatted with a woman at AK on Thursday who told me she had been seeing "drops" for Tiana at around 48 min past the hour pretty regularly on days it was running well (no storms, no major down time). On the two days I didn't have Tiana booked, I was able to snag one for the exact time I was planning to be in MK that day between 9:45-9:48. On another day, I was able to shift an afternoon time that was a bit of a PIA to a perfect time in the late morning. These were definitely drops of new times, as they lasted for a few minutes and were offered at more than one time slot, it seemed to me. YMMV.
2) The ability to do major overlaps shows up on the day of your park day, at 6 am EST. It also seemed that new times were opening up then for day-of. I recommend having a leader get up at 6/6:30 and adjust as needed/wanted, which brings me to #3.
3) Talked about it videos, but reiterated here - book whatever attraction you can, Tier 2, whatever, at the first available time, preferably right as the park officially opens. Have your entire party badge into the ride as early as possible during the window, This will unlock Tier 1's , as people here already know - importantly, the earlier, the better, as this gives you more time to modify.
4) It is easier to modify a ride than book a new one, since modifying allows you to see your "pinned" attractions, and using Molly/Mammoth's "megafaddle" approach, it becomes very powerful (to visualize this, I recommend watching her videos). So once you tap in - just grab something, anything that will give you some time to modify for something more desirable, if you don't see your top choice at the time you want.
5) If your top choice is available at a cruddy time, grab it - that will be at the top of your screen as you modify, so when a better time pops up, it will be easy to snag.
6) Otherwise, use the remnants of the old Genie tool (look for stuff like "Plan for your day" with a teeny Genie icon), and go through the exercise of selecting your top attraction in the parks you'd like to visit that day. To be as fast as possible, I would recommend picking one, 2 max, per park. When you get one, go back through the exercise (using the old Genie tool) of deselecting/removing the checkmark next to the ride you now have and selecting a new one.
7) Seemed like you could get last-minute stuff right around the time when you might anticipate people wanted to leave and do something else - think, times of day when kids were starting to get antsy in the parks (say, late morning in MK right now is a boon, since the heat gets stupid) or when rain starts.
I mean it when I say we were able to do everything we wanted with almost zero breaks in between, it was ridiculous. I want to be clear that I did spend time on my phone, and maybe more than some people would wish to, but I never ran down my battery to the point where I needed a charge. Once or twice, I sat in A/C for a few minutes modifying, but I was able to get everything I wanted, at convenient times. The caveat of course: end of August is not end of December or Spring Break, which are busier and will draw more "competition" for LLs.
I truly hope this helps people who are super-stressed about prebooking. Having a Tier 1 prebooked you want at a time you want going in is ideal, but do not sweat it if that doesn't happen!
(ETA - adding that I also think people who don't want to spend time on their phones are going to be at a disadvantage - sorry....
