Okay, this one was fun. The presentation was simple but effective, but the gameplay was spot on. The driving felt smooth and the enemy intelligence was perfect. Annoying enough to hit you when you need it the least, but dumb enough to let you slide just in front thought the corner.
Definitely keep the 3d-rendered esthetic. Maybe look at 'Super Skidmarks' for some inspiration, that game had a higher POV / smaller vehicles which could allow more players. But more importantly, it had a caravans that you could hitch behind your car, maybe you could implement that you carry the oil drum/powerup behind you once picked up, then waiting for the moment to blast someone in front of you literately becomes a drag, which then should change the sweeping around the corner physics, like really flung the back and some slow down through the oil. (powerup/trade off)
If you really want to pursue this maybe change the focus from solely targeting BP and more like take all the big ecological disasters as each stage and educate the player before the stage what crap we did and the impact (and name BP there) and the after the race the state now/what happened afterwards. Edutainment is much easier to get funds or sponsors for. I just hope that if that works out, that there will never be a sequel or DLC. ;)