You make good points, and the Servo team is doing more or less as you described. Our primary target is 64bit and we plan to leave behind lots of legacy stuff.

You make good points, and the Servo team is doing more or less as you described. Our primary target is 64bit and we plan to leave behind lots of legacy stuff. The extra parallelism we're after also enables new things too. For example, Servo runs cross-origin and sandboxed iframes in parallel.