What a sweet face!!!

I have never been crazy about outdoor only dogs, however, I do know that some are very, very happy and would actually prefer to be outside.

I think providing a loving home even if it is outside is a better option then a high kill shelter. Becuase I know you would give him the shade and water and food he needs, I think you should keep him.
Maybe you could ask around or see if there is someone else intersted that would be able to make him an indoor dog, but with just the options of high-kill or with you, I say keep him!