Layered Hebe - What to do with it now?

Hello

I found a branch of our Hebe had layered/self rooted so I cut it off and planted it in a large pot. It looks kind of silly though, this fully leaved hebe branch sticking up out of the pot on its own. I'm wondering whether i should hard prune it back so i just have a rooted short stem that will eventually branch out and form the natural mound shape? or should i just leave it and it will eventually send out shoots which will catch up with the existing branch?
I'm figuring hard pruning it now will also help the roots expand as they are only short so may well struggle with all the foliage on the branch.

Many thanks for any help

Tree

 

How tall is it treetops. If it's under a foot, I would prune it back by half, if it's larger, take off two thirds. Hebe's need to be pruned to make them branch and fill out.