Propose UI for centered search as a configuration

I'm not a big fan of having too many UI options in XS because that would clutter the Admin UI a lot and we have extension points and skins to do this. Thus I'd like to see the needs first and to understand better why the existing solutions don't work. I haven't checked the code but I'd expect the search bar to be a UIX, and replacing that UIX with a custom UIX to center it, or simply providing a SSX to center it, seems very easy to do.

Now, if our search bar is not well-placed and it's better to put it centered, then that could be ok too, but we need a rationale and to agree about it.

Thanks