Well, I can't decide really either ... I ike her in anyway.
I think it's true that if she stoped smoking and wouldn't expose to the sun that much her skin would look more 'fresh'.
But I found out that this is also in her genes. Look at her girls ( and Louis also, but not that much) they get extremly dark skinned in summer, and they are not constantly lying on the beach...it's natural at them. I believe that even if Steph doesn't tan (on purpose) by lying on the beach her skin would be that dark.
About smoking...well, it's hard to give up once started...so that might be really difficult.
I believe she looks great anyhow. It's ok if you're 40 years old and you look like a 40 year old , you don't have to seem younger by force...and she doesn't look older then her actual age.