I think your best bet if you can get a stock plate and steel to replace the spring plate. that will give you one extra clutch plate, so you have more surface area, just leave your stock spring see how it goes. everyone different as we are all different sizes and weight. but try to get away with lightest spring pressure you can makes shifts faster easier and riding in traffic easier. keep away from the aftermarket plates I found Harley plates in stock clutch to be the best.

if you want a really good clutch bandit machine works make some beauty's I've has bandit super clutch and I've has an s&s clutch both good but had them in big twins think bandit has sportster clutch too. but more clutch than you need.