Please don't make the (very common) mistake of reducing an entire beautiful, varied artform down to someone strumming frantically over a 4/4 rumba beat in a minor key. This is like saying Michael Jackson is heavy metal music just because Eddie Van Halen played on one of his songs once, or that Tiny Tim is Hawaiian music. To be completely honest - at least in the U.S. ukulele world, as far as I know - Daniel Ward and I are the only ones with flamenco street cred who've actually studied flamenco and played (guitar) with flamenco singers and dancers. We know the structures ("compás") and I have yet to see someone aside from us play a proper flamenco rasgueado and in anything other than 4/4 time. My friend Ben Woods (R.I.P.) made a fun
video playing one of many flamenco styles (there are many, rumba is not officially one of them) called bulerías and although he is playing with a pick, which never happens in real flamenco, Ben knows this and has already proven himself as a flamenco player many times over. The only time I play flamenco on ukulele is when, just for something fun, I'll play Sevillanas onstage with dancers at the Los Angeles International Ukulele Festival. I do this because I want people to see the dancing, the costumes, and hear the singing and the compás and say "ah...so this is flamenco". See pic below
Best thing you can do if you're interested in learning some basics of flamenco is to check out the solo compás videos on YouTube (used to be all on CDs). I think you'll be surprised to hear what flamenco really sounds like. Learn what's what and then adapt to ukulele. Here are some suggestions:
In the spirit of Christmas, check this out - this was from just a few days ago, my friend's husband is one of the guitarists. It's a very traditional thing you'll hear and see all over Jerez in concert halls, nightclubs, Elks Lodge type clubs, etc; note the 6 beat structure:
¡Felices Fiestas!