I don't mind not having 'imperial world' - civilized worlds tend to subset down as hive, shrine, industrial, etc - or at least an acolyte's life experience would.
War world & Agri world spring to mind
Rogue Trader Dynasty
The Navigator (navigator mutations)
The Pilot (operate-based bonus)
The Mercator (commerce/social)
Astropath (bolt-on to psyker)
Rogue Trader (high-level elite advance equivalent to inquisitor)
Cannot the Sage role be also user for a commerce career ?
I think you wouldnt need an additional Rogue Trader Elite advance.
If you had the background trade cartel, you could combine it with the highborn homeworld to create a RT.