Perhaps not feasible due to contractual purposes, but I think grid customization would be a neat feature for players who like to focus on their own personal narratives within the Formula One sphere.
Basically transfers, but done manually by ourselves. An example would be something akin to FIFA, where you can change a player's team and save that data on file if you choose to use it.
I play full races online with a friend. Being able to change up the grid based on their performances in that season of ours for the next season would add charm and realism to the play through.
I'd make it possible in Grand Prix/Championship mode, as well as unranked online lobbies (restricted to friend rooms, maybe?)
The pool would include current F1 drivers, F2 2019 drivers, and the current F2 drivers if they are added.