The show did revolve around her too heavily imo.
You can't blame them really though, the combination of Jeri Ryan + Catsuit became a cultural icon, i mean she was everywhere back then, magazines, billboards etc.
Personally I think it was overdone on the show though, and I also feel she had very poor character development in the 4 years she was on the show.
4 years is a long time, and she was still very much the same person at the end of it that she was at the start.
I look at Seven of nine as a child when she was first separated from the collective, in the 4 years between, she didn't "grow up" at all