Well, already two medium on the back, you can put a launch bay maybe ? Or just greebling for say than this guy have a small more energy flux or cargo!, if you add a launch bay, he go have no cargo for fuel or supply.
Apologies, forgot to explain.
The Venture (GM) is going to be an 'anchor ship', so to speak, for my race car faction the GMDA. While all the other ships are GOTTA GO FAST, with high speed and maneuverability in exchange for low armour, vastly reduced cargo and fuel stores, and practically non-existent CR peak time, this one will be (comparatively) slower and have a longer CR peak time. So while all the other ships are crashing and burning, this one will still be around to give them fighter cover. It'll be a lot more expensive to deploy, recover and maintain however, as it's supposed to be a heavy 'capital' cruiser.
Right now I was thinking three flight decks out the back (IE the really dark grey bits), 2 Ballistic mediums on the outer wings, 5 small composite turrets, and two medium hybrid hardpoints on the front. Was originally thinking of sticking a medium energy turret on the back to add more tactical variety. Now I'm thinking two medium missile hardpoints, in the larger grey 'voids' on the back between the blue armour, pointing out at 45 degrees, and changing the front hybrid hardpoints to ballistic.