as Chris says above.
I started with a Ducati single with drum brake (hardly working, used rear more than front), then got my license on disc brake bike. never had a new bike, always old Ducati's with drum brakes. the best one I had was a Condor A350 with 200mm lump drum front and rear (interchangeable, neat!). in due course came a pantah and parallel twins, KTM's and larger Ducati's, all with disc brakes, and those are needed with the increased power and weight.
I've sold ALL my modern bikes and kept the old bangers for their charm and ride them almost daily.
the vin has much more power than the brakes can decelerate in the ever shortening stopping distances created by most pathetic egocentric blind wankers wearing baseball caps sideways and their windows bulging with every beat from their stereo's in their BMW/VAG cars; if not being cut-off from <censored> in their VAG/BMW/Volvo/French cars with optional indicators...
so improving brakes on an ol' banger is not the reason to get a modern bike, but to save yourself from others creating the undesired circumstances. that's why most got a license: its your GCSE in "how to avoid randomly generated obstacles on the road" course.
sorry if I get a bit carried away on this, it really really annoys me; have been hit-n-run 2x already by these types, and 4x by Volvo/bmw office <censored>. yes I have a thing against European and xxxvo cars.
besides, braking ability is a higher priority than speed in my mind...