Care to recommend some dog breeds?

We currently have a three-year-old female orange tabby and a one-year-old border collie mix. We don’t plan on getting another dog for at least a couple of years, but we’re trying to figure out what dog breed would be best.

I’d like our next dog to be small or medium sized, but I’m open to some larger breeds. No Great Danes, Pitbulls, or Mastiffs. Nothing ugly like a Pug or too high maintenance like a poodle. We want a down-to-earth, loving dog with a medium energy level. A dog that doesn’t need to constantly be with people (we both work) or need a ridiculous amount of exercise (a daily walk is all we can manage). A dog that typically gets along with other dogs, cats, and children. A gentle dog that won’t howl or yap all night. Preferably, not a dog that sheds profusely, since our dog takes care of that on her own. No breeds known for bad health problems. Now, I know I’m asking for a lot, and there may not be a breed that fits into all of these, but I just want to hit as many as I can.

We’ve discussed Yorkies (I hear they can be aggressive with other dogs and kids), Beagles (I hear they’re hard to train), and Siberian Huskies (they shed quite a bit). That’s just what we’ve talked about, though, not the only ones we’re willing to choose from. I also know that not every dog is different, but I’m just looking for common characteristics within breeds.

And no suggestions for a mutt, please. We’ve got one of those already.