I've found that, by following these principles, I almost never have to wait more than 10-15 minutes for any attraction, regardless of crowd levels.
1. Arrive before rope drop (unless unnecessary, see below)
2. Use FP+ for the most popular attractions you plan to visit on a given day (subject to tiering requirements), such as SDMT and FEA (helps if you stay on property so you can be eligible to reserve 60 days out)
3. Use first hour in park to ride standby on the most popular attractions for which you didn't reserve a FP+, visting in order of popularity (i.e., based on what builds largest line fastest)
4. Have at least a 6 day ticket, which enables splitting MK and/or EP into at least 2 days each (and divide those parks into pieces)
5. Be satisfied in visiting most, if not all attractions (especially the most popular ones), only once
For example, we have an upcoming spring break trip, for which we have 8 day tickets. We plan to spend 3 days at each of MK and EP and 1 day at each of HS and AK. At MK, we divide the park geographically (1 day for Tomorrowland, 1 day for Fantasyland, and 1 day for Frontierland+Adventureland). At EP, we divide based on Tier 1 FP attractions (1 day based on FEA, 1 day based on Soarin', and 1 day based on TT).
The only day we have to be to the park well before RD to avoid any long waits is our HS day (in order to ride both R&RC and TSM without signficant lines). On our Fantasyland and Frontierland+Adventureland MK days, we'll try to arrive a little before RD and on the rest of our days, it's not critical to arrive at rope drop (especially our EP days).
The one thing that can mess things up, of course, is if an attraction is down when we plan to visit. But that's just something we try to roll with, given it's a variable we can't control.
Otherwise, the above strategy is practically foolproof, even during the busiest seasons.
(FWIW, we are go back to our resort in the afternoon people)
1. Arrive before rope drop (unless unnecessary, see below)
2. Use FP+ for the most popular attractions you plan to visit on a given day (subject to tiering requirements), such as SDMT and FEA (helps if you stay on property so you can be eligible to reserve 60 days out)
3. Use first hour in park to ride standby on the most popular attractions for which you didn't reserve a FP+, visting in order of popularity (i.e., based on what builds largest line fastest)
4. Have at least a 6 day ticket, which enables splitting MK and/or EP into at least 2 days each (and divide those parks into pieces)
5. Be satisfied in visiting most, if not all attractions (especially the most popular ones), only once
For example, we have an upcoming spring break trip, for which we have 8 day tickets. We plan to spend 3 days at each of MK and EP and 1 day at each of HS and AK. At MK, we divide the park geographically (1 day for Tomorrowland, 1 day for Fantasyland, and 1 day for Frontierland+Adventureland). At EP, we divide based on Tier 1 FP attractions (1 day based on FEA, 1 day based on Soarin', and 1 day based on TT).
The only day we have to be to the park well before RD to avoid any long waits is our HS day (in order to ride both R&RC and TSM without signficant lines). On our Fantasyland and Frontierland+Adventureland MK days, we'll try to arrive a little before RD and on the rest of our days, it's not critical to arrive at rope drop (especially our EP days).
The one thing that can mess things up, of course, is if an attraction is down when we plan to visit. But that's just something we try to roll with, given it's a variable we can't control.
Otherwise, the above strategy is practically foolproof, even during the busiest seasons.
(FWIW, we are go back to our resort in the afternoon people)