Is KLyDE some official project for a light KDE? Because when I google for it, I can only find your post above.
A couple weeks ago I experimented with a "light KDE" solution. I think the Slax developer Tomas M. did some very nice work in trimming KDE. Give his latest Slaxk 7.0.4 a spin, and you'll see the result.
Here's the Slax source code:
As soon as I finish my Linux training here (in about two weeks), I have a series of projects pending (besides taking a weekend off). First one is making such a trimmed down KDE desktop. I have KDE4 (thanks AlienBob) running on a machine here. Basically the idea is building KDE without Konqueror and Kontact, and use Firefox, Thunderbird and Lightning. Leave out the desktop search (Nepomuk, Strigi) as well as Activities. There's a bunch of KDE apps I really like using daily (Gwenview, K3B, KSnapshot) and which are best-of-the-breed. Others are a bit too bloated for my taste (KTorrent or Kopete for example), so I replace them by apps like Transmission or Pidgin).