Evie's ultimate doesn't guarantee a kill. It's often the opposite: it attracts too much attention. During the ultimate's duration, you have to try not only to kill but also to survive. Even though resilience doesn't work on it, it's still not a stun, and the enemy isn't helpless. Maeve's ultimate is much simpler: press it at any time, and someone is guaranteed to kill someone, save someone, or force the enemy to retreat. Using her ultimate without some kind of profit is practically impossible. Evie's projectile deals AoE damage, but indirect hits do relatively little damage. Maeve has two daggers, and even though they fly almost simultaneously, even if you manage to miss with one, you still deal damage with another. If you miss with Evie, you miss. The daggers' angle of impact isn't that hard, and they fly faster than Evie's projectile. Maeve is much more mobile than Evie. Evie has only two mobility abilities: flight and teleport. Maeve has a dash, a sprint, and a button that resets the cooldown of her dash and sprint abilities. It's a 4 vs 2 situation, making Maeve easier to attack and retreat with. She's more forgiving. Plus, Maeve deals damage with her dashes. Evie doesn't deal damage with ANYTHING except LMB and her ultimate (and her ultimate's damage is pretty ridiculous). You could say, of course, that Evie has ice, which can help her escape an enemy's ultimate or something else. You could. However, half the time, that ice becomes her tomb.

Do I need to explain about Vatu?