There's no such thing as a perfect figure. Though they're getting better. You should see all the fixes for Victoria 4 there are. Dawn 2 is going to be released soon, presumably with some built in fixes.

I bought Perfect Pelvis when it was on sale for about half the current price. I've never used it, though. I don't often render images where small glitches in the pelvic area are visible.

There's generally a trade-off. When La Femme came out, someone complained that her naughty bits weren't high-res enough. He needed them for what he was doing. Most people don't. A lot of polys and morphs in an area that won't even show when she's dressed is a waste for many users. Dunno if there's a solution for La Femme yet, but for previous Poser figures, the solution has been a separate add-on.

If Dawn's hips are too flawed for you, and you don't want to buy a fix, why not stick with La Femme? You seem happy enough with the way she bends, so why not just use her?