Is a sense of humor a good thing? It is an appropriate response in some situations, but an impolite one in others. That is the easy answer to the question. but the overarching, more black and white question still exists: When it comes down to it, the only possible answers being yes or no, is humor a force for good or ill? I almost write evil instead of ill, but didn't. These two words mean very different things. Evil categorizes a construct as abrasively negative; an abstract looking-to-do-one-harm phenomenon. Ill is more general than this, allowing for negative externalities, but not giving them an origin or starting identity. It can be passive or accidental.
A person with humor can use it to draw attention to himself as well as away from himself. He or she uses it as a tool. One must ask himself if this implies that the intention of use of the tool is good or ill instead of the tool itself. After all, a sickle might be used to harvest grain or hurt an individual. But a gun or sword has really only one function.
But is a person without humor better off than a person with? It's important here to say "better off" than "better." I think that humor is such a main part of current society that a person with no humor would experience very potent intrinsic and extrinsic anxiety to conform. This might lead to some kind of self-destruct.
Humor is a great pressure-release, especially when heard. I think that most people, when discussing humor, mention only the comedian. But what about the audience? Humor heard has the ability to decrease anxiety and depression levels.