DO NOT PURCHASE A BUELL BLAST!!!!! They are poorly manufactured garbage. I could tell you stories, and not just mine! I've always loved the Suzi GS500. It's a great lookin' bike, theres a billion of 'em and they can handle. If not a Monster 695/secondhand 620, I'd look for one of those. I've always disliked the look of the beginner Ninjas. People keep the Suzi GS500 but everybody is desperate to dump their beginner Ninjas. Perhaps that's why there's plenty immaculate ones everywhere. Red Baron was implying I recommend my '82 Honda Magna as a starter bike, but I won't. First of all you'd do well to start her sporty and then learn to cruise. Also cruisers are much heavier bikes with vastly inferior handling. If/when yer girl decides she's no canyonista, then let her trade to a cruiser. If she does insist on a cruiser, get a small old rice cruiser like the V30 (600CC?) Honda Magna. Old Japanese bike are bulletproof, plus you can get an IMMACULATE one for two grand.
My two bits,
-Dan
P.S. Nighthawks are sweet bikes too!