It's still a good asset to keep. Just the people

who are renting, usually are poor (or temporary). They need a basic living place rather than enjoying the house. Their payment ability or interest cannot match up the house's quality.

Your another one's return ratio looks fair. 

Another thing I want to point out is that your house distributed too widely. I prefere to group them together in one or two areas so that I can have a portafolio of contractors/handymen that I can easily utilize. It makes me easy to understand the neighborhood as well. 

Gu-shi