The E205 actually is a good idea for sure, from experience. I've used it on a straight wing "oldie". Well, it was actually a straight wing with slight LE and TE taper that was E205-E193.
What gave us fits was getting the AOI correct. Incidence seems to have more effect when the wing is carrying a bulky fuselage that probably isn't exactly low drag. I'd suggest having your rear wing rod be adjustable in the fuselage.