ECS is really only different from OCS in that it has more chipmem for animation buffers (Joyride, anyone?)
Haven't seen one that takes advantage of the extra chipset features.
On OCS, a coder's skill could usually be measured by his ability to make fast vectors. Some demos made coders go 'how the...?'
1. Vector Preview by Tai-Pan/CPX
2. Hunt for Red October by Tec/CRB
3. 3D Intro by Tai-Pan/PHX
Some coders steered clear of 3D and did other skilled things (impossible playfields, animation buffer tricks spring to mind). It's cool to make something impossible
which is an illusion ofc. There's also something to be said for those who spend days and weeks optimizing and rewriting a single effect to attain 'impossible speed'.
Tropical sunset by Silents is one of the early 2-D greats.
In later years, I saw an intro with a flight through seemingly fractal clouds in beige tones, but I always forget the group, so if anyone wants to refresh my mind...
And ofc, there is no denying Arte is a stylish, meticulously programmed trackmo. I love it, especially the vectors at the end. What still has me puzzled is how they "filled the horizon" when it's diagonal (fills the screen). Since the vectors aren't interactive, perhaps the whole scene is pre-calced and pre-clipped to save fills, but I doubt it.
The first vector thingy I saw on Amiga was vectorbobs, in the classic MFC intro. It takes someone to come up with stuff like that. No idea if they were first, but I intend to find out
Speaking of just that, one coder stands out. That coder is Celebrandil. He was first with a lot of things-- Transforms in the Interpol demo, Sawcut in Animotion, good raytracing... the reason, I think, was because he excelled at math.
I probably missed a bunch of demos and coders, but it's getting late... bedddd... soooon...