I am debating running a fantasy game using the CODA system (What can I say I love it guys, it really addresses every single issue I had with D&D) but I find that I want a bit more spell action (not mechanic spells but cool fantasy game spells)
Why don't you just convert the D & D or D20 Spells that you like to the Coda System? Some of the Coda spells are close enough to whats in D & D so that you could make some intelligent decisions about how to convert. Create Light, Lightning Bolt, Flame of Arnor/Flame strike and Transformation/Polymorph Other come to mind.