Royal Single Speeds
Avant garde is the front line. Someone has to be making something that really pushes how we view our bikes. I don't think there are any production bikes currently that do this and I am not familiar with custom builders. But an example of something production could be the Trek Y foil except that it isn't SSFG.
Anyway I think this is a bad way to talk about bikes because it isn't how I view or use them. my everyday transportation/utility and exercise use doesnt demand anything special. Pro racers see that spectrum of bike design, just take a look at TT bikes and the Hour Record bikes, and that is so far from me.
Anyway, in my last post I linked to a bike that is a bit more expensive tht the ones you posted but IMO a lot better and more interesting.