I think we are going to have to agree to disagree about this. I didn't find the Harry Potter books nearly as engaging or riveting as The Hunger Games books and I have absolutely no inclination to reread them or to see any of the films once I knew the ending of the series, which is the opposite of how I feel about Collins's work. And I find Katniss an extremely strong female character, not in the sense that she's always perfect or right, but in the sense that I find her completely compelling. I haven't read Twilight, so I can't comment on that comparison.

ETA: I do understand how you feel (albeit in a slightly different way) because I loved the first two books of Philip Pullman's trilogy and absolutely hated the last one to the point where it spoiled the entire series for me. I just have absolutely the opposite reaction to the Collins' books.