Create an extension point to be able to fill the header

At the moment there is no possibility to have an element centred in the header except in aligning element on the left or the right in using extension points like org.xwiki.platform.template.header.after ; org.xwiki.platform.topmenu.left ; org.xwiki.platform.topmenu.right

As an example I'm trying to add a Carousel in the middle of the header.
It's either floating on the left, either on the right. I'm missing a way to have it centred.

Attention :

• Since the center is gong to be filled, the search engine will have to expand hover this central section instead of pushing the full rght stack under the central part. (screenshot made using org.xwiki.platform.topmenu.left)