He's a lovely looking lad. Greyhounds and other sight hounds must be the easiest going dogs around. My parents kept a series of Italian Greyhounds (like yours but very much smaller) and they were all fantastic pets, but I was particularly fond of one called Hamlet who was as game as they come. He would chase anything that moved, and usually caught it, but lost interest once motion stopped. He would run after a ball if you threw it, but if it stopped moving before he got to it he'd come pottering back and you had to go and pick it up yourself.I'm a veterinarian and I see the the love and affection my clients have for their pets on a daily basis. I'm definitely more of a dog person myself and have a 12 year old retired racing greyhound myself. I definitely get where you're coming from as I see his energy spurts gets shorter and shorter and see him lose some of his strength. Thankfully he's otherwise is pretty good health.
He also liked to run around in the snow, even though his paws would turn blue with the cold. And he was one of very few dogs I've met who could sit on your shoulder.