For the past year I have been planning a family vacation to Disney World for all of my kids and grandchildren. The trip happened last week and I have to say we had a great time. We did a few things different on this trip than in other vacations at Disney World. One change is that of Genie+ and I thought I would weigh in on if it is worth it or not.
In January I visited Disneyland with my oldest son and his family. It helps to compare and contrast that experience with Disney World as the service is available in both parks. My hope is that it will help you as you plan your summer vacation as both parks seem to be very crowded now that COVID seems to be slowly going away.
If you go to the Disney parks to ride the rides and money is not a concern, then by all means add the service to your ticket. It will save you long lines for at least a couple of rides. If you are a little more discerning with your cash then you may want to pick-and-choose when you pay for the convenience.
I opted not to pay for Genie+ for any of the days at Disney World last week but then I wasn't concerned with riding rides. I really went to hang out with my grandkids and have fun with them. None of them had Genie+ and so it didn't make sense for me to pay an extra $15/day. I will confess that on our last day in the parks, I got stuck on the Pirates of the Caribbean for 30 minutes. Disney immediately gave us 2 free lightning lanes that we could use on half a dozen rides. Naturally I couldn't use it on any of the thrill rides like Space Mountain or the Seven Dwarf's Mine Train. I did enjoy being able to skip to the front of the line for Thunder Mountain Railroad and The Little Mermaid ride. Then we loaded up our car and headed to the airport.
My son opted to pay for Genie+ while at Disney's Hollywood Studios where he used it judiciously. My philosophy was to get to the parks early and save myself long lines and I got to ride a lot of attractions in a short time.
Ultimately my recommendation is not to add it to your ticket every day. There are some parks that don't have a lot of Lightning Lanes that allow you to jump to the front without waiting. At Disney World, it is only a $15/day addition (it is $20/day at Disneyland). You can add it in the Disney World app on your phone and then immediately schedule your first attraction. As you can only have one reservation at a time, make sure you don't sign up for a ride that allows you to jump lines at the end of the day. That can be expensive for a single use.