@BOTMAN There's a saying, "those who can, do, those who can't, teach." Well. It's also true that those who can do, and those who can't hate. Professional haters.
The Number 1 girl is right, the MC is actually exceptional, he's mastered all adventuring skills up to intermediate rank. So even if he's hit or is approaching his natural limit, that still means by definition he's probably the second strongest person in the room besides herself. He really is an extraordinary person. He just feels inadequate because everyone from his old party was world class specialist. And even then, those world class specialists very much owe their world class status to his support abilities. She was right to ask for him: if there was ever a good choice of partner for a high level solo adventurer, it would be an intermediate-to-advanced all-rounder with strong support abilities. Which is exactly what he is.
Hopefully we'll be seeing more of her in the future. She has a somewhat ditzy personality, but she's clearly not stupid. I enjoy that. She's happy-go-lucky, but not idiotic. I like perceptive characters.