I am so glad that we seem to be starting to crawl out of the minimalist local minimum.
The one thing that I remember about Aqua, was what it did to performance.
Before OSX was released, we were seeded prerelease copies, but with the original System 7 UI.
It was really fast.
When the first Aqua release came out, the performance dropped like a stone.
That sounds like Rhapsody/Mac OS X Server (which would have been Platinum). And it is, indeed, quite snappy. I have it on a Wallstreet G3 and it runs very well.
Liquid Glass seems to hearken back to that era...