IMO, which is worth exactly what you`re paying for it (i.e. nothing) you`re waaaay overdoing it. More is not always better and you have an awful lot of SiO2 products lined up to use. While I have no experience with CK UK 3.0, my inclination would be to do 2 coats of CQ UK 3.0 topped monthly by one of the products in your title. I have used the PA Cosmic Spritz and Overcoat extensively but not Viking Coat.
Both Overcoat and Cosmic Spritz have excellent hydrophobic/self cleaning properties; Cosmic is a bit easier to use and has a sharper, more blingy look and I think Overcoat has a very slight edge in durability/self cleaning with a bit richer look.
Given both of their excellent hydrophobic qualities, topping with Echo2 or Clutch could actually diminish those effects but can`t say for sure as I`ve never used either.
For a month or 2 over the summer of 2017, I tried washing our coated car with Gyeon Bathe+ (SiO2 enhanced wash), doing a final rinse with Gyeon WetCoat and then topping with Overcoat...it was, in my eyes, pointless and offered no benefits over just washing with regular Bathe and topping with Overcoat.
Hopefully someone with more experience with CQ UK 3.0 and it`s best complimentary products will chime in as I can`t speak from actual experience with most of the products you intend to use. Also, sometimes things don`t work so well together and you`ve got 4 `coating-ish` products lined up before you even get to Overcoat or Cosmic, from 3 different mfg`s (4 including the Cosmic and Overcoat) and there`s just no way to tell how those are all gonna interact with each other. You could end up with diminished performance (or, who knows, maybe you`d end up with a `super-coating`). I topped another mfg`s coating with TAC Moonlight once and it gooned up the self-cleaning so bad, hadda polish off the coating and re-coat...a real PIA. Since then, kinda gone with a minimalist approach of coating+topper and life has been better (and cheaper).
Just my experience and, as always, YMMV.