Body Fat Percentage Factors

Options
I've been trying to figure out a good body fat percentage goal for myself, and I'm having trouble figuring out what would be a good goal for myself. First of all, my current body fat percentage is a lot higher than I expected. I'm definitely far from a fitness model, but I have been working out regularly (both heavy weight lifting & cardio) and eating clean (most of the time - good weeks and bad weeks, yall!) for awhile now, and I have some clear definition. Judging by pictures and some of my friend's stats, I was expecting to be 24-26%. I'm at 29% (this is according to a body fat monitor at my gym. Online measurement-based calculators have told me everything from 23-31%).

My original goal was trying to get down to 18-20% body fat... but now I am starting to wonder if that would be a good goal or not. One of my friends, who is a super fit chick with 16% body fat, told me anything below 22% would look too intense on me. She says since I naturally have a pretty voluptuous shape, my body fat percentage is always going to be on the higher side.

So, basically, my question is this: how much does a woman's chest and butt size play into body fat percentage?

I want to gain muscle, be lean, and feel fit & healthy... but I'm not looking to be in any fitness competitions and I'd like to hold onto my womanly figure. I don't want to set a goal too high and become obsessive or totally frustrated with not reaching it. At the same time, I don't want to make excuses for myself or set a goal too low just because "I'm a curvy girl."

Advice? Feedback?