On the ram speed thing I would like to say that the intel 6 and 8 core cpus have had IMC speed problems since launch in 2011. The facts are that AMD are officially supporting a faster speed than intel on day 1 of launch of a brand new 8 core cpu architecture. This is a huge accomplishment which should be applauded.
Also, raw MHz is not everything, a tightly timed 2666mhz kit can outrun a 3xxx MHz kit given the right timings.
Lastly I would also point out that I no longer use ASus motherboards of any type simply due to their fault rate and bugs. This is not limited to Ryzen. If you want a top board come back in q4 when no doubt we will have a Asrock OC formula to buy.
I would agree with you were the speed of the link between core clusters not linked to the RAM speed as it is in Ryzen's case. It would have been great if this link were independent of RAM speed and user adjustable, if that's even possible, then it wouldn't matter as much what kit you bought.
I have a 5820k with 32GB of DDR 4 2133 with tight timings and dual sided (my bandwidth scores are about 10% higher than single sided kits) and it's fine, not far behind my old 16GB 3000 MHz kit in Aida64.
I agree with you about Asus, I've had two Asus boards: the first, a P4C800, worked perfectly for two years before failing. My current Asus Sabertooth X99 has been giving me all sorts of issues(it's either the CPU or the board I've eliminated everything else) whereas my Gigabyte X58 UD5 lasted 6 years, maybe I'm just unlucky when it comes to Asus.