Spip is a wonderful CMS.
I'm using it for http://10aout.co.cc at x10hosting.
Before ou do any more work on your site, upgrade to spip 2 (last version, as of this writing, is 2.0.9). Whereas upgrading spip is usually very simple, to go from 1.9.2i (last in the spip1 series) to 2 is trickier (read spip-contrib forums), sop you might as well avoid this work by starting right from the start. If you dont like the standard spip interface, you need to add a squelette. I recommend sarka or eva or epona, but I haven't tried them all. What is your site?