The problem is not with the drivers but with userspace daemons - Jack and Pulseaudio. Both of them really need realtime priority (on one of my systems, the quality of sound output through Pulseaudio is horrible unless I make it realtime), but both daemons are typically launched by a user, not by root (since that makes for much easier desktop integration).
So the solution is to either
a. enable rtprio limits for your normal user account (something that I am forced to do, but which carries obvious security risks); or
b. design a secure mechanism for granting realtime priority to specific processes, using policykit or some similar mechanism (which is what Lennart is doing with his RealtimeKit).
Obviously, b. is the correct solution, and I applaud Lennart for trying to make Linux sound Finally Work Right.