Since Hughes openly admits to being a professional cheer person, then there is nothing unethical about his work. Hughes makes it a fun experience for fans in the stands and this also motivates the players. Hughes is paid to do this and everybody knows about it which makes it a legitimate job in my opinion.
Yes, I believe professional cheering is perfectly acceptable. Professional sports teams are businesses. Hiring someone to stir up excitement and good will among fans enhances fans' experiences at games, helps improve teams' morale, and is just good business. Professional cheering in no way affects the rules of play, so it poses no ethical challenge.
With regards to professional cheering being ethical, I see no reason why it would not be ethical. He has a unique talent and seems to enjoy working with that talent. Who are we to stop him from using his talents in a positive way and bringing joy to thousands of people. Now, when I look at it as a fan of multiple sports, I do not agree with it as much. This is essentially the ultimate "bandwagoner," and any true fan will probably tell you they do not like "bandwagon" fans. So, I really see no problem with this from an ethical standpoint, but being a sports fan, it is a bit irksome.
Professional sports announcers are like journalists. They supposed to be impartial. They are supposed to present the information in an objective way so that people can make up their own minds. Instead, Hughes has decided to act as a professional cheerleader. It is not ethical for reporters, even sports reporters, to tell people what to think.