I'd say I like hearing more of Nicole's singing because it's what got me interested in the current KARA. She's always so modest when it comes to her modest, but I love it when she gets chances for solos, or features in songs like 'Happy And'.
That said, her unique, foreigner (yes, I said it) rap is an irreplaceable feature of KARA's music. Also, it's become a part of her character to me - I can tell what kind of person is through her 'rap'. I have to admit that I always start grinning when I talk about it because it's one of the cutest styles I've ever heard, but hey, I was never much of a fan of conventional rap anyway.