I agree. I got my friend (who's a medical resident and doesn't have a ton of time, but has an awesome dog) a subscription to Fuzzy. They do exactly what you're suggesting with preventive care. Their service includes an in-home well pet exam and all the vaccines, flea/tick and heartworm medication the pet will need until their next preventative visit. Obviously, outside of a clinic with equipment, they're not really able to do anything too involved: giving vaccines and taking blood/stool samples is about the limit, but that's all that's necessary for a healthy pet.

We had a good experience, and my friend's dog loved the vet and the assistant who came to examine him. I think the pricing was similar to what it would have cost for an in-office appointment.