Why haven't we heard about her? For one thing, she doesn't really do much stuff that is worthy of media attention. And maybe she doesn't need to try to sell herself to the world like most of Pac's "friends" do by making DVDs about Pac or doing interviews and shit, which I respect.
The only time I recall hearing about her was once in TIME magazine, a bit after Pac died. It had her saying that in the end, Pac was maturing and just chilling at home watching laserdiscs of Les Miserables and stuff rather than going out all the time. She talked a bit about Makaveli, saying it was way better than most of his stuff since she said it was "about lessons he'd learned."
But yeah, I saw a pic of Kidada and Rashida, I think Rashida is prettier and more of a strong woman (as seen by her response to Pac talking shit on her family back in 1994 or so), which Pac respected. Too bad Pac didn't meet the right one at the club.