Well, it depends on wether you drive RWD or FWD cars, and where their engine is located.
FWD cars have the bias more to the rear, as engine braking will increase front braking anyways.
RWD cars have it more to the front, because engine braking brakes the rear wheels.
Front engined cars also have more brake strength at the front, where the weight of the engine increases grip, vice versa for rear engined cars (which you don't have in the demo anyways).
Soo, besides that, we can obviously see that "most car games" != LFS
In LFS 65% brake balance is way too much to the rear, altast for the demo cars. For these a value between 70 and 80 is ok. You can easily test it by going full throttle down the straight, then hit F (activates the force view - hit again to deactivate) and start braking (in a perfectly straight line if possible). If the rear wheels start locking first (red "arrows") the brake bias is too much to the rear. It's much easier to drive if the fronts start locking first, but ideally (for drivers with digital brakes) the wheels shouldn't lock at all, even under slight turning. Granted, you lose a bit at brake distance, but the increased stability will make up for it.