Your trees are making great progress! Also looks like you are learning an awful lot about these persnickety plants.
And persnickety they are, often tossing foot long soft branches, creating taperless sections of trunk without intervention and curling their leaves while one is getting a coffee refill!
In our neck of the woods an aphid attack on crabapples, cherries and the like is fairly rare, maybe roses on occasion. The thing crabs get the most (in spring) if one doesn’t stay on top of is rust.
Best
DSD sends