I once did a lot of reading up on this to figure out why I essentially can only have one (very boring) hairstyle as I have a heart shaped almost oval face which in theory should be able to carry off any hairstyle.
It's not so much face shape but how much of your parting is visible alongside that shape. So people like Naomi Campbell, Jessica Biel, lots of models, basically known for having strong faces don't display much of their parting when you see them face on. Jawlines tend to be wider more masculine but it's not a set rule.
Then you have what is often typecast as the girl next door, Jennifer Aniston, Reese Witherspoon, Sarah Michelle Gellar, Farah Fawcett, etc. that show much more of their parting and it makes for a girlier feminine perception of their features and the face appears smaller, closer together, 'cuter', as the hair really wraps around it but the individual features can still be quite pronounced since there's less space, but it also means bangs are harder to pull off. Jawlines tend to taper, are smaller, heart shaped, diamond, etc.
Then there's many who just fall in between, they tend to be quite versatile. Think Zoey Deschanel with the bangs and the actress who played Christine Keeler on that recent dramatisation of the Profumo affair, she could really carry those 60s volumised styles off with ease despite having quite a modern face.
With age hairlines recede and therefore we all tend to look a bit harder, if you add regular Botox and filler to the mix that stretches the forehead even further back and you get those women who end up looking like medieval paintings. Hairlines make much more of an impact than we seem to notice.
With CG you see the different types as well but it's more difficult to assess with all the masses of hair piled on and the hair not laying flat. I've noticed the ones who probably have little visible parting, like Curly Cailín, they tend to do that exaggerated side part that's quite far out to get the same rounded volume around the forehead to cascade down. I tried styling it like that once (I'm of the lots of parting on display, flatter in the back sort) and wondered why I looked so bizarre until I twigged onto that. The ones with more visible partings tend to have the haircut I have with layers being key at the front and keeping the parting closer to the centre (or dead centre) so it falls around the face. I don't think there's an ideal here (perhaps just the balanced in between for ease and versatility) as they each have their own accentuation of beauty but it's just something to keep in mind.
Good layers at the front make a big difference to me, I don't have razor sharp cheekbones but they are a feature and sit moderately higher, be it a softer sort. The way Japanese and Korean women often have it. My face goes a bit shapeless when the layers have grown out and I look more of a non descript oval, when the layers are doing their thing my face has much more dimension. Sounds a bit similar to you Sophie