I quite like BRs, but think they may be over-used (on a times per race basis). Perhaps better balancing by making them cost more shields? The activation method is too unreliable though, I'd much rather have it bound to buttons than the analog stick (switching to dpad doesn't count). I'd say overload the airbrakes, but I hate that SS overloads them already; I've lost count of the number of times I've SS'ed by mistake while making minor turn corrections. Having L1 and R1 purely as 'stunt' keys - tap L1 to SS left, R1 to SS right would be good, but people probably quite like them as rear view and comms... Looking for controls not used yet we find... the right analog stick! Tap it Left or Right while on the track for SS and push it L or R in the air to BR. Might take a bit of getting used to, taking your thumb off the throttle, but I think it'd work pretty good - a lot like dodging in God of War.

Anyway, an option for hosts to disable BRs in their multiplayer games would be good, as would an option in the control setup to disable SS entirely (I'd much rather not be able to SS at all than keep screwing up corners due to accidental activation).

EDIT: alternative to Right Analog: use the 6axis - a violent jerk of controller left or right - to activate SS and BR.