So I gather you're not using any modelers?
We're talking 4ms max here. In physical world terms, that equals 1.3 meters. Do you have your cabs mounted straight to your head and can we have a picture of that?
This can happen with any setup. I had more amps going down than digital devices during gigs. And that's what backups are for.
I want to never stop twiddling.
No, I don't need it at all. This proposed setup is all about "want". In terms of what I need, I could've stopped around 3-4 years ago already.
So this entire thing isn't even remotely driven by real demands but purely by something that I want for fun.
Never. The sounds I'm getting out of that stuff inspire me to play more and they inspire me to play different things.
Have a look at your very own Sunday Ambient series. Is that following the EJ approach? Not at all. And yet you seem to be having quite some fun, plus it generates a lot of musical output. It's basically the same thing, really. Just that I'm using a guitar for things and can as well use the setup for any traditional tones as well - which, in return, will even be the best tones I ever had and super easy to deal with as I will be the one to define all the ways how I like to deal with them (global blocks included, just as one practical example).
I did exactly that for one musical show and later on expanded it a bit into a hybrid setup for another musical show.
I stopped using it because a) it was only really decent in an orchestra pit, b) under very controlled musical conditions, simply because there was too little CPU juice available back then to allow for some leeway, so every patch had to be programmed per tune and I couldn't slap much "just in case" stuff in.
Later on it got a short ressurrection, I was then fooling around with a modular host (namely Energy XT, which unfortunately stopped being developed any further), but CPU power still wasn't there.
And I also used my Macbook for two gigs that came up when I wasn't expecting them, so I had to travel there from my parents home where I fortunately had my Rig Kontrol with me.
Anyhow, all of these gigs went absolutely fine. But things have been severely limited in terms of sound quality, sound choice and handling. These days, that's completely different, my actual MBA could possibly run 20 of those rigs on one single CPU core.