Well, since last update, I have reconfigured all my network and half the devices on it, have done full factory resets on all devices (atom, muso, Qb 1 and Qb 2) and things seems better. Both actions seemed to deliver some improvements.
I had a new Ubiquiti Unifi AP which was seemingly a root cause of some of the issues - I exchanged it for multiple wired and wireless TP 1300 AP devices and many of the direct connectivity issues are much better - (so thanks guys for pointing me in that direction - it was defo part of the problem) - we are not 100% cured, but miles better.
Please let the imminent update rumour not only be true, but the update be actually working, as I so want to love everything about this brand. Naim - if the update works then just gotta fix the communications and you have a very happy customer again.