It's actually obvious that Wellmy is prettier than Iora, but since Iora is well trained in etiquette she appears more elegant than Wellmy plus Iora is the legitimate child of their family so even if Wellmy is prettier the other nobles would probably choose Iora since nobles values legitimacy.
Also, Wellmy didn't actually put effort to in learning etiquette and other things noble should learn because she doesn't want to attract attention in a positive way, she literally wants other people to perceive her as a vain woman with only a pretty face (just like how the cp perceive her).
When it comes to intelligence, both of them could be considered as genius in different ways. Iora is a type of genius who could easily learn everything, while Wellmy is a type of genius who has a very logical mind since she thinks like an adult at a young age, it only appears that Wellmy is not a genius because she works hard. She actually has a good plan, its just that she is so kind that people who knows her true self saw through her plans. Aside from that, as what Aides and Iora said, for me, Wellmy is better because she is brave enough to put her plans through actions.
Also, Wellmy always says that Iora is better than her. That Iora can easily be the rank 1 in their school if not for the abuse, but I think Wellmy is not below to Iora, they could be equals or they might even be a chance that she could surpass her. Wellmy actually has a lot to prioritise as well to focus solely to studying, she has to deceive her parents, deceive the people around her, entertain Iora's fiance, make sure no bugs goes close to Iora, planning the downfall of her family and etc. It's true that Iora is better than Wellmy in any magic as well as magic research, but Wellmy is better than Iora in support magic. Both are gifted in magic, they just have different specialty.
All in all, both are very special in their own way. It will only manner to people's preference to choose who is better than who.
*matter
You're right.
I still can't get past CP's obliviousness to Wellmy's intentions, though that could've been blinded by love. More people caught on quickly while he supposedly watched her for a while
I shouldn't compare the sisters, but they harp on Iora's beauty when I think Wellmy looks way better. Iora looks plain compared to her, even in her dressed up mode.
Anyway, I love that this is a story about sisters who loved each other against the wishes of shitty parents and other outsiders. They never lost sight of each other.
I still don't like the prince, even though they tried to explain his dislike of Wellmy. He was still jumping conclusions (and missing Iora's true aim/personality).
(￣ヘ￣)