There's no reason that you shouldn't be able to step, as long as it's something that the people in your chapter want to do and everyone in the chapter has the opportunity to try it out if they're interested in it. It's a fun way to build unity and have fun together. I get a little annoyed if it's not creative (e.g. a chapter uses specific elements that are already associated with other groups on their campus) but otherwise, why not?
I can see some potential downsides, depending on the campus. Some potential members at schools with ongoing racial tensions might be turned off by it, but I don't see it having a huge impact on recruitment in most cases anyway, and I would hope that most people interested in joining APO would be open-minded enough to respect people in the chapter that wanted to step. Also sucks a bit (from an individual perspective) if you have no sense of rhythm but want to try anyway.
I guess I didn't see any Asian traditions because, for us, they were just APO traditions? I mean, one time my chapter did Korean hip hop for roll call, and we help out at a lot of events that are somewhat targeted toward Asians (like the Chinatown YMCA run and dragon boat races), but yeah. And some of the other now-gone traditions *cough*Mr. and Ms. APO*cough* were not inherently Asian, I don't think. They were just strange.