Binary package hint: kubuntu-kde4-desktop
I've noticed that in the Kubuntu-kde4 alpha (which I'm using), there are several KDE3 applications preinstalled to take the place of KDE4 applications that don't yet exist or aren't yet stable. Examples: koffice, adept, jockey-kde (the new name for the Restricted Drivers Manager), network-manager-kde, etc.
The problem with this is that, not only are the additionally KDE3 libraries loaded, but there is no visual integration whatsoever. What I suggest is to instead use GTK applications (or unstable KDE4 applications). (Examples to replace the previous ones: koffice-kde4, synaptic, jockey-gtk, network-manager-gnome, etc.) This may sound counter-intuitive, but just hear me out.
First, there is no doubt that there is no visual integration with KDE4 and KDE3 applications. Second, the KDE3/QT3 libraries will still be loaded in addition to the normal KDE4/QT4 libraries. Third, if you are going to load additional libraries, why not load GTK ones (they are more lightweight than the KDE3 ones if I'm not mistaken)? Fourth, there are far more GTK applications out there than KDE3 ones that complement the existing KDE4 ones (Gimp, Firefox, OpenOffice, VLC, etc.).
Finally, my main point: near-perfect visual integration with GTK applications is not only possible, but is being achieved by me and many others right now (look at the attached screenshot). I have Firefox 3 (though I did go into /usr/lib/firefox-3.0b3 and change all the Firefox icons to Konqueror ones), xfce4-terminal (Konsole crashes dbus for some reason (I'm on amd64)), Synaptic, file-roller (Ark doesn't detect the contents of subfolders for some reason), jockey-gtk, PCManFM (for some reason Dolphin and most other KDE4 apps can't be run as root), and Gimp (Krita is nice, but I learned on Gimp and I'm used to it's UI (yes, I know that's very unusual)) running alongside my KDE4 apps perfectly with near-perfect integration. The only problem is that I couldn't find a working GTK icon theme that replicated the Oxygen icons, so I settled for the Mac4Lin icon theme, which is still very nice and still goes well with KDE4. I know it could be better, but the GTK theme I used (called 'qt4') can be found here: http://www.kde-look.org/content/show.php/gtk-kde4?content=74689 (I never got the 'gtk-kde4' app working, but the GTK theme is excellent).
Anyways, I hope you consider my idea, because it really is the only logical choice when you really think about it (unless I'm missing something..). Oh, and by the way, the fonts should by antialiased by default, because non-antialiased fonts really do look awful.
Typo, should be: 'not only are the additional KDE3 libraries loaded'