Ok, so we’ve just got back from our trip and despite it being Spring Break (and on one day we were there they actually closed MK to park hoppers because it had reached ticket capacity of 100,000, the first time it had happened since 2021), we did not buy Genie+ or ILL once and still rode everything we wanted.
We rope dropped every park at least twice meaning we got straight to the big rides and had minimal queues for the other rides. You might not want to rope drop the whole time (we rope dropped on 9 of our 11 park days) but certainly for the first 2 or 3 days you are going to be waking up really early, so you might as well take advantage of it and get to the parks first thing.
As you are not staying on site you won’t get the option of early entry (30 mins extra before the park opens to everyone else), but you can still enter the park at this time and either check out the shops or position yourself for what is known as “second rope drop”. This is how it works:
Assuming park opening is 8am, the Disney resort guests will be allowed to enter Fantasyland (where the most popular rides are 7 Dwarfs Mine Train and Peter Pan’s Flight) and Tomorrowland (Space Mountain and Tron, though you need a virtual queue or individual lightning lane for this) for a 7.30 start. HOWEVER, they actually start letting everyone into the park just after 7am - the early entry guests go through an additional check point near the castle while the non-resort guests are held on Main Street and around the castle. Here you can position yourself near the entrance to Adventureland which will allow you to get access to rides like Jungle Cruise and Pirates of the Caribbean, or Big Thunder Mountain in Frontierland, as soon as they open at 8am.
If you are only doing 1 day you need to do your research, plans out which rides are must do for you and then work on the basis of doing those that have the longest average wait times as early as possible, as the wait times will only keep going up through the day.
I can also give you our virtual queue strategy if you want - it never failed us, and we got to ride Tron 3 times (well DH and DS did, me and DD weren’t up for it!) and Guardians (in Epcot) 4 times during our stay!