Charde is not the only player to improve significantly after UConn. In my opinion, Tina Charles became much better offensively after her college career, mainly by developing a reliable mid-range jump shot. It is also notable that she led the WNBA in rebounding in her rookie year, despite often falling short of her rebounding potential during her UConn career.
In neither of these cases should one conclude that there was a deficiency in the coaching received by these players at UConn. More significant factors are: (a) greater personal maturity in the years following graduation, causing the players themselves to realize the importance of developing additional skills and the desire to put in the work necessary to do that; and (b) better "chemistry" with their WNBA coaches -- not everyone has an ideal personality fit with Geno or CD.
I think, on the whole, it was a mistake for Charde to have come to UConn, and for Geno to have offered her a scholarship -- and I think his recruiting selections since then have suggested that he believes that also, and is determined not to repeat that mistake. No one from a personal background similar to Charde's has been recruited since she graduated.
Tina is a different case. I think she simply grew up emotionally and personally at a slower pace than many players, and didn't fully develop the determination to realize her vast athletic potential until at least her senior year at UConn, and perhaps even after graduation. Geno made a wisecrack once about how coaching Tina was like sending a message to a distant galaxy -- it would be years before the message was received and responded to. He predicted that she would come back after she is married and has children and say, "Now I understand what you were trying to tell me when I was playing for you." As usual, his observation was probably very close to the mark.