I would still choose to set up your Fastpass Plus times. Also, be aware that you can change them and times are still available on the day of visit for most attractions.
It looks from your signature that you have only been to DL, not WDW.
One thing to be very aware of is that WDW parks are MUCH bigger than DL. Things are much farther apart and there are not many places to sit (and the ones that are may be occupied). So finding a place to sit after 10 minutes of walking is going to be very difficult.
There are also attractions where, even if you use the Fastpass line, you will be doing a combination of walking and standing for more than 10 minutes without having a place to sit. Do your plan of walk for 10 minutes, sit, walk for 10 minutes, sit might work at a smaller park like DL, but you won't get very far that way at WDW.
That is one of the reasons Disney suggests assistive devices like wheelchairs for people with mobility related issues.
You may want to consider an assistive device even if you don't use one at DL:
- a rollator - it's a walker with wheels and a fold down seat. So, it provides support while the user is walking, which can help to walk longer without stopping. When you need to sit for a while, you can put the seat down and sit.
If you want to go without it into a line, you can park it with the strollers.
- a wheelchair - many people use one like a rollator. Someone can push you in it to a general area, then you can park it with the strollers if you want to walk without it, or push it for support and a place to sit when needed.
- an
ECV - many people use one to cover distance and get to a general area, then park it and walk in that area. When they leave the area, they get back on the ECV, ride it to the next area, then get off and ride.
My FIL had issues similar to you. He could walk, but it was a slow toddle and he had to sit and rest often. But, he had bad hips and if he sat on benches for long, he could not get up. So, very similar to your situation.
He found over the years that there was less and less he could do since he could not toddle far enough into the park.
He missed out on a lot.
The first time he rented an ECV for the day was the first time in years that he had lasted past 3pm. It was also the first evening he had not spent in pain, with ice packs and pain killers. He said he could not believe how stubborn DNS how stupid he had been and he rented one after that and had many happy trips.
So, some things to think about. I'm not saying not to use
DAS; it's a tool that can be very helpful, but it can't do everything you need.
You may not want to do a mobility device, but a mobility device is just another tool that might make a big difference between just enduring your trip (while your family goes on ahead) and actually enjoying your trip with your family.