I have both of these noises on my car and I haven't been able to fix them yet.
#1 I think my version of your problem may be my brake pads jumping around in the caliper. Try applying the brakes lightly and hitting your favorite bump; did the noise go away? It did for me! Now you just have to learn to ride your brakes under 40 mph.
#2 I found the exact same issue with my car last year. Since it only does it when shimmying at stop condition, I stopped shimmying the wheel while stopped (it still annoys me though)! In all seriousness, it sounds like you've replaced or checked a lot of the usual suspects and some of the things I thought about replacing.
I'm very curious to know what you are able to find on either of these issues. Keep us informed of any progress!