(Image: Caldwell Tanner)
Caldwell Tanner, the cartoonist who made this flowchart, is definitely a dog person. In fact, he recently appeared in a video explaining why he and his girlfriend adopted a dog from a rescue shelter.
(The best part of the video is when the actor played Bane in The Dark Knight Rises gives his approval for the adoption.)
But on to the flowchart: yes, if you want a companion, then a dog is your best bet.