The rootball of this meyer looks different from the other citrus I just repotted. There are lots of fine roots and it was harder to work with than the open rootballs on the others.

There was a dense layer of fine roots across the entire surface. Seems like a good thing, but maybe too dense? It was a separate layer from the rest of the rootball. Also made it tricky to get the new mix in the cavity that was formed below it.

After washing with a jet of water (lots) and a bucket swirl, this is the result.

I put it in 5-1-1, but after recent comments, I am considering pulling it and washing even more.

Is there any root pruning that could be done on such a rootmass?

Here's the tree; I think the form is pretty nice, although the top was cut off and now there are 3 branches which I may be sorry about later.