OK, I get the anxiety thoughts. I remember when the town tore up our street for weeks while they ran new sewer lines. Everyone was upset. But the old sewer lines were inadequate, and with new homes popping up, it was an improvement that needed to be done. How does Disney improve their parks, when their parks are open 365 days/yr?
Some people are worried about FP+. I have concerns. To me, it's strange and new, and I guess I'm having a normal human reaction to that. We'll see when we get there. Fantasyland work has been going on for 2 years, and most visitors in the Fantasyland area seemed to be upbeat and curious about progress on the other side of the temporary wall, because they knew it represented enhancement of park facilities. Unfortunate for OP that his family will probably miss the opening of Seven Dwarfs Mine Train by a few weeks.
Now there's Hub construction. It may be difficult or confusing to get around with construction walls going up, but I've seen a plan what they're trying to do, adding wider pathways and more people space--less water space. Anyone whose ever watched Wishes can vouch for how over-crowded the Hub is at that time. Adding more space for people should be an improvement everyone will like.
OP, if you feel this time is not right for your visit, because of the construction and the unknowns about FP+, I would seriously consider postponing your trip, perhaps moving it to next Spring.