I'm just throwing this out there, what about a Delta Rallycross series?
I don't know if I could host it with all the DRC craic, there is now 3 games on Delta with a rallycross game mode: DiRT Rally, DiRT 4 & Project Cars 2. The DiRT games have a better multiplayer setup for RX but PC2 has more RX cars & circuits.
Again this is just an idea if someone wants to try make it happen.
Although DiRT 4 has the full RX event for multiplayer, heats, semis & final along with custom liveries, I also think PC2 would be the best choice. More RX tracks & cars, race director, broadcaster & spectator functions, team liveries for possible team championship & of course, one of the standout features for PC2, variable weather.