Maybe he meeds some trimming back to fill in . What do others think , or maybe it needs more sun., or both. I have never grown them. It looks healthy,

I don't grow it either, but from photos I've seen it seems like that is it's natural growth habit. As Mara says it looks healthy so I'd just leave it alone unless it's wilting a lot. In that case perhaps it doesn't have enough roots to support the top growth after it was moved and trimming it back would bring it into balance. On the other hand, a lot of my established plants started wilting from the afternoon sun after enjoying so many weeks of unusually mild cloudy weather. They will toughen up after a few days.

Here is a link that might be useful: Images of bottle brush trees looking top heavy ...