PATTERNS OF FORCE was described by someone at the IMDB as "the serious version of A PIECE OF THE ACTION". That's about right. Unlike the alleged "parallel evolution" of THE OMEGA GLORY and BREAD AND CIRCUSES, the gangster planet and Nazi planet were both the direct results of Earth missions contaminating the indiginous cultures. Of course, this meant in both cases, Kirk was free to "interfere", since he was trying to put right was was put wrong from previous interference.
This was one intense, nasty episode... and yet, unlike B&C, it's eminently watchable, even entertaining. I wonder, maybe Nazi stories are easier to deal with than Roman Empire stories, because in WW2, there were, in the long run, much greater powers poised to take down an obviously insane, hate-filled, self-destructive country... while, with Rome, there was nothing to stop them (apart from a mesage of peace and brotherhood, which itself became perverted when a Roman emperor decided to CO-OPT it as his new STATE RELIGION).
I can't see the joke being a problem, since SULU is the one who said it.
This exact same thing cropped on on TERRAHAWKS all the time with "Hiro", who ran Spacehawk. His boss, Dr. Tiger Ninestein, was a real P**** who often made fun of Hiro's Japapnese accent. More than once, Hiro would toss it right back in his face. Sometimes this involved the use of "pidgin English", when Hiro probably spoke English better than Tiger. (I recall Charlie Chan doing the same thing at least once back in the 30's-- and he was ALWAYS the most intelligent character in any of those movies. His doing so wound up making fun of the ignorant.)