For me it sound reasonable to remove Hybrid from the car in terms of cost saving. If I am not mistaken, one unit is ca 15% of the total car cost. And in most of the rallies, more than one unit is used + charging infrastructure + support engineer from Compaq Dynamics, + etc. Next reasonable step would be likely prohibiting carbon use in the parts that get destroyed most frequently (starting from bumpers, door sills, front fins, etc. Maybe a few other things in lower part of the car. You loose the weight with hybrid, gain a bit with cheaper plastics, loose a bit of power. With these rather simple solutions you can reduce car price and running costs quite significantly