We took our twins at almost 3 (and again at almost 4).
I agree with
@MNtwinsplus1mom that if it was THE trip, I would not choose that age. Not just for memory reasons, but because it is too stressful if your goal is to do EVERYthing.
What worked best for our family we found was 2/3-3/4 days with them mostly being rope drop (am EMH) to one FP+ to lunch to 2 more FP+ and then leave and go back to resort for pool, nap, quick service type dinner. We chose ONE fireworks/late night activity each trip (so that day was sleep in, pool, head to park around 2-3 with FP+, dinner, fireworks). I originally tried the rope drop and then afternoon break and then back our for dinner; however, ours took forever to get to nap and then didn't wake up well and we were stressed getting to dinner and it was not a fun experience. Also, while we used Child Swap a few times because we had an older son, it was much easier just to concentrate on rides we could all do.
Mine did a really good job staying with us and not running off. They were just naturally more hesitant in that strange, huge environment. We did do safety tatts, though. We also utilized the stroller.
We had to have the attitude of just having fun, not getting every second and every cent out of the vacation. It was fine if they had the most fun watching Disney cartoons on tv or going in the Tiki Room 5 times.