I’m a bit stumped…I think I understand your problem but forgive me if I have got confused!
The only thing I have found having 2 sets for one bike is that I have to align the brake calipers for each set. I have no idea if this is always the case when changing wheels or if you have such an issue.
I agree the hope hub is a noisy bugger, hated it for the first few rides but now not so bothered.
What is your front hub that you have to use?
Thing is if you are going to end up with a great all round wheel set spending the cash on Flows will that be more than getting another set for racing? Would they even be a good race choice(flows)? I wonder what light race wheels you could get for 120-150, maybe superstar have something?