Carl, best advice on these little things, especially with Asphalt, enjoy the understeer and work with it a bit more. Id try M grips on the front, you still want a little push, and gradually find more steering. As soon as you go past the point that the rear stays put ie it starts to loose rear grip at all, your done lol. They are a blast when you get them right, but promise, if you can creep up on the steering, youll do better. Are you guys limited to Tamiya tires? Id check into what the guys in Oz are running if not, and work from there for sure. Ive hardly run any asphalt (all indoor for me) but if your S grips are working for you on the rear, again id go with something like a M grip possibly, and id even be keen to try the CA glue trick on the outer edge to avoid the tire rolling completely. id also change to a red spring in the rear, leave the white in the front, and again, slowly creep up on more front grip.

Both my 04 and 03 (and hopefully my 05) are completely dialed on carpet with the same tires. I planted the rear, found the BEST tires for grip, and slowly mess with the front. If i go too much (like too much tire sauce on the front on carpet etc) then i go back and try something else. Its a fun test, but the best peice of advice is stick the rear at all costs.

Also i know RC-mini dont feel there is any difference when changing the length of the mini, but id get yourself a swift or better yet a civic body if they allow it, and run the mid length. Ive always found the mid to long WB a little more forgiving myself. HTH Carl