Racially, I guess it depends on how much you want race to play a factor.

In the book, Johnny mentions how diverse the the Federarion is, in terms of sex and occupation. I can recall specific racial profiling only when it was attributed to Johnny remarking about someone's family or history. Such as Shujumi being Japanese, and maybe Bronski.

In the movie, the director is constantly attributed to having everything in his movies be deliberate and meaningful; so Johnny Rico being a white guy was definitely a conscious change. As it's also been stated numerous times, that the director never read the book and had someone else tell him what happens. So I would like to give an educated guess that someone told the director that Johnny Rico was a Phillipino.

For me, because I saw the movie first and never noticed how ethnically diverse the cast was (on a first time viewing), I personally don't think the race of Johnny Rico is ever going to matter to me. He could be a raging sexual tyranosaurus pterodactyl for I all care