I take it you understand the term and just want to know if handling them differently is possible.

As with many things between Japanese and English, once you get down to the small word modifications and word play / variations there is nothing much you can do.

There are a large number of greetings in English - Hi, yo, hey, all right, how you doin'?, hey there, what's up, how's it going?, you're looking good, nice to see ya, how's it hanging, what's going down? etc. etc. Although many of these are significantly longer than the Japanese you could get across the informal nature of the term with some of them.

If you pick a greeting for each and use them consistantly that will at least give you consistancy. But there is no way to accurately render them all branching from the same source word unless you create a new greeting specificially for that purpose.

Hope some of this helps, anyway.