Gotta get another 2 cents here - Thin air-foil, design optimized for "hover" flight is the way to go if...the goal is to produce a competative .15 carrier design. Heck, just get permission to kit Bill Bishop's "Sniper" design - not a bad idea, actually. But, if the goal is to produce a more versatile design, one may want to consider a fully symetrical airfoil - and a more attractive design. Regarding the airfoil, a medium thick symetrical airfoil would give the modeler (customer) the option of building a carrier plane or... a sport/stunt trainer. This would broaden the appeal of the design and
who knows, maybe the plane will foster another racing class.
As far as carrier flying goes, it could still be competative at the level of its target market, beginner or intermediate carrier. Personally, I would de-emphasize the "hover" flight aspect for the beginner. Let them fly fast, fly slow, and learn to make a scale type carrier landing. Not that difficult and a very satisfying maneuver. My son was WAM junior champ (twice) when he was 13 and 14, only event he flew was profile carrier but made every landing using this style of flight. Later, the leadouts could be moved back and a hover style developed - after interest in the event was developed.
Regarding the choice of designs: I'd rule out the Spitfire and Zero. Love both of them but they are pure low wing designs. Mid wing, shoulder wing, and even high wing are more stable in low speed, probably having to do with the vertical CG. OK, the Helldiver and Hellcat are not exactly mid wing but the wings sit higher in the fuselage than the previously mentioned designs. Also mounting the wing through the fuselage rather than gluing to the bottom makes a sturdier wing mount. Of the H-Cat and H-Diver, I prefer the Diver, only because it is rarely modeled but the Cat might be more attractive to a beginner modeler and, squared off wing tips (Cat) are easier to build than rounded tips (diver).
Reading this post over - I was thinking .15 when I wrote it, but most of everything would apply to 1/2 A as well.