Jim,

There is site with a lot of old plans from the 1930's - 1940's you may like. Several larger OT's that have to be scaled up and designed to be silk covered (and some rubber powered that look like they may be nice conversion to electric park flyers). While they where designed as FF, you'll have no problem adapting them to RC. There's a few I'm going to draw up.

http://www.theplanpage.com/

Hogflyer