My initial response is almost always to say get bigger. But that isnt what everyone desires so shoot for what makes you happy. If that means putting on some size then maybe now you are at a time when you can do it. But if you prefer to be thinner and do not like the added weight you are putting on maybe you should try to lose some of it. Not that you need to do cardio for that though. I actually find cardio has an overall negative effect on my appearance.