If a store card is something that can benefit you greatly, ie, you always shop there and the rewards add up with specials and such, then go for it when you are ready. If its just to have a Kohls just because, not a good idea. Definetely work on your utilization before adding more credit cards because if your scores are still in the 500s after 6 years with no baddies, you are only holding yourself back from getting the credit you deserve
. Just mho