I didn't mean to say that Omnisphere is an 'ambient synth', as I said, I've never tried it. However, they are a number of synths out there that are termed as such and an awful lot of libraries, loops etc. that are described as 'ambient'. My point was that I choose to make my own sounds and I find it to be one of the most stimulating elements of ambient. When I was studying, I was exposed to electroacoustic music techniques and a big part of that is the sound design element, it's an 'anti-preset' music if there ever was one. I took this from the genre as it was probably the only thing that resonated with me in the whole 'eam' thing.
On the tools point, I flippantly referred to the Strat as only having three sounds - but it has a massive potential to use all manner of playing techniques to create anew these basic 'presets'. Saying that though, I've heard some synth presets that do sound great, but you know that because they have such instant appeal, they may well be used considerably - unmodified.
No problem with the 'venting', it's good to see more discussion hereabouts !