I think a pragmatic RRA would have to focus on volume of materials used in production because a big team's advantage comes from knocking out multiple options and variants.
Then it doesn't matter that Ferrari or McLaren have huge buying power for CF due to their road car programmes, while a back of grid team might have to pay cash on delivery. Equally it doesn't matter if Ferrari have 10 people wearing Gucci to making mouldings compared to a bloke in a shed for a back of grid team.
We know they limit the size of wind tunnel and analysis computer (both hardware and solver size).
Policing design resources would be a nightmare. You'll never be able to pin down where IP originated.