Bring back the open world/freeroam of FH3, where we had stuff to do beyond just drive around and PR stunts. There were credit bounties, AI hunts, and AI convoys that went a long way to making the open world feel alive when playing solo.
The game feels desolate and dead now, even with the added traffic in solo mode.
PS if new open world activities can be thought up, all the better. Just make sure they can be ignored like the other stuff or else they become obnoxious.