My most favorite model sailplane is obviously the Aquila. Still have one which was built in my dorm room in 1979 (needs a little repair to one wing inner leading edge... damn fence jumped out in front of me....
). Have a Grande N.I.B. to build sometime.
I also love the Graupner Cirrus. I still have one I got used in the early '80's and flew in Open Class, plus have the remains of a second.
Also on my build list: Magnum 12 (have one N.I.B.), a Mirage (always loved the look of the original color scheme), and a bunch of scale ships: a large scale Orlik (Polish sailplane from the '30's, actually got to work on the only surviving full size), Libelle, Kestral, and last but definately not least the Slingsby Petel.