I tend to like runners/bikers more than weight lifter types as well. It's all personal preference, especially in keeping dogs, and as long as the dogs are happy healthy and not stressed, it's up to you.
I keep Enzo on the thin side. She's a Lab, so I've gotten used to comments about her being emaciated, too skinny, don't I FEED my dog for christs sake?! and I just ignore it. When Enzo is zooming laps and butt tucking around the park, and their dogs are laying around because they're too fat, I feel like, I'll probably get to enjoy my dog for far longer than they will, and that's what matters to me.
Ozzy is kept in the normal range. I can only see his last few ribs if he's flat out, but he's got some serious thigh and chest muscles. I should probably keep him a bit leaner, but he seems to feel the cold in the winter when he goes swimming, so I let him gain about half a pound to a pound or so. I don't worry about it, because when summer hits, he goes back to being ripped with playing flyball and disc dog stuff at home.
I haven't had Knox long enough to really get a feel for how he'll do with weight and conditioning, but he's a GSD, and his coat hides EVERYTHING. You can see his ribs because he's a sable, but when I got him he was a hair too fat, and he was a bit flabby. He was at a good weight, but he had no conditioning at all, he couldn't keep up with the other dogs, he got tired really easily. Now, he can run around for much longer, and he's actually building some really rock solid chest/shoulder and thigh muscles.