in my experience going from doing not a single thing 4 years ago and now a regular gym goer and fitness instructor, cardio will help you loose the fay over the muscle, and by no means does this mean you are fat. Weights will help you with toning. I did a combination of the two and for that 3-4 times a week was ideal 2 weights and 2 cardio's. However this gave me great results but it was doing Yoga that really made my definition in my muscles stand out. It was when i started that the compliments started coming so if this is your cup of tea maybe something to consider.

Yoga will also help with flexibility and length which will also help the muscles to look leaner, as well as the health benefits to you body and mind that yoga also creates

hope this gives you another idea