You are reading what other people have written about him. When people are negative against an individual they are going to write negative things.
So, you never met the man personally which is why you can't speculate using absolute statements.
I've known several people who felt uncomfortable around a certain group of people and acted serious. When they were in their own environment and loosened up their demeanor and personality completely changed. They were joking, enjoying themselves, and were having a good time.
So you can't come up with a single example of Oswald having any sense of humor. Got it. What point are you trying to make? That Oswald wrote "Hunter of Fascists, HA HA HA" in Russian on the DeM BY photo as a joke on himself? Do you think he thought of himself as being humorous in that photo? My point was that the sentiment is more aligned with Marina's view of his erratic behavior. Thus, she likely wrote. Why don't you stick with your endless political rants and leave the discussion of the JFK case to others?