A long term redesign of the software could definitely be beneficial.
We have done it twice, without much benefit. I'm all for evolutionary way.
Actually, we'd never have made it this far without the "revolutionary" redesign done by Lee earlier this year. Our performance old PHP code was breaking under far less load than we have all the time now.
While, we do need to improve our DB performance, but without better stats, we can't say for certain that there aren't any PHP bottlenecks. And PHP bottlenecks could eventually arise if we improve DB performance significantly.
I'm all for the evolutionary way, but I think there's room for someone who wants to work on a revolutionary way while others improve our current system.
Yours Mark Christensen