Mine didn't get "meaty" until after they were two years old. Perhaps yours haven't grown into that stage yet. Don't let them!!! LOL!!! We have dieted ours for years now, to try and get them to that perfect weight. As long as they are eating, don't have any other medically related symptoms, enjoy feeling their ribs and don't think "chunky". I am the exact same way as you, as I want them to have some meat on their bones, but mine have too much and as they get older, they do slow down and fatten up, especially after a spay/neuter.

Logan