Is it time to prune or just let it grow?

It is time to provide a bit more information…..

Oops thought I included the pictures

What do you want the tree to be in the future? One dont prune for the sake of pruning, one prune in order to achieve a goal for the tree.

I second Tropfrog, you should have in mind what you want for this tree in the future.

But I would definatelly make some selection prunning to prioritize the worthy branches in there, starting to prepare some structure.
It seems overcrowded, however, like Tropfrog said, you must have a goal, for example, if you wan't to thicken and later hard prune very low, you just shouldn't bother with it's top.

It's very common to see materials for sale that were just prunned to have a bushy look.