Which dog breed should I look for?

I am currently trying to decide upon which breed of dog will best fit my interests. Primarily, I want a dog that cam run at least up to 5 miles with me on a daily or every other day basis. Athletic prowess is definitely wanted. But I also want a good companion. Loyalty: A dog that will ride shotgun with me and have a calm side. Smart and trainable. Also good with strangers. I don't want to go over 50 lbs, and don't want to go under 20. A soft coat is desires but not necessary. I would be willing to sacrifice a little athletic prowess for better companionship an ease of training. Some breeds I have considered- Irish setter (a little on the big side :/ but everything else is great) whippet (really cool dog! But don't know much about the temperament) Aussie (had one for about a month but had to give him away because of heart problem, couldn't afford the surgery :( ) any suggestions or experience with these or any others that seem fitting? Please throw out any breed you think might be a good fit.