Aloha,
I see....you want to AutoX the bugga. Hmmm. Well, I would be in favor of building the smaller displacement engine in that case. The 69mm crank might not launch like a stroker, but it will wind up faster (depends on your rods and cam too). I think keeping yourslef in a class that has definite rules as to what can and cannot be done to the drivetrain is to your advantage. If you go in an unlimited class I think you would be setting yourself up for disappointment. Yes, you can make a lot of HP in a ACVW, but like you said, it depends on the car that can go into the corners faster and leave the corners faster. I love ACVW's but they just don't have the reputation of being a well handling bunch (for road racing at least).
aloha,
Joel