4 parks in 2 days is actually very manageable. I did that over Christmas in 2014. We might not have chosen to fit all four in, but my Dad was with us and we wanted to show him all 4 parks. We did some highlights in each park, took a relaxed pace, and had a great time. Also depends on what kind of tickets you have. For us, we have non-expiring hoppers. Since hopping is already included, it wasn't a financial cost to hop. Last month, my nieces chose to do MK and AK with 2 day base tickets. They would have liked the other 2 parks, but their must-dos were concentrated in those 2 parks. They had the time to hop, but the add-on cost was high and they decided it wasn't worth it.
I would suggest talking to the kids and asking their must-dos. Once you see everyone's must-dos, you can make your plans accordingly.
Then after that, be flexible when putting together your plans. Our last trip, my must-do was Star Wars fireworks. We only had one park day and I started off planning to do all 4 parks in one day. But Star Wars fireworks kept stalling my dinner plans. Finally, DH decided that a relaxing dinner with our nieces (who weren't going to be able to go to the fireworks) was more important. So I cancelled our DHS plans. DD was a bit bummed about missing RnRC, but it ended up being a great call and we had a wonderful dinner.