As much as I'd have liked for it to not be the case, Kaede's not good. The superficial assessment of budget Yurius doesn't convey how much weaker her debuff is.
Skill 3 applying AoE debuffs and having a fast animation is nice, but one random debuff per cast is unuseable level. Yurius stacks 40/40 down with 40 meter on the first turn, Naoise stacks 40/40 down on one target on the first turn, and Monika stacks 30/30 down within 2-3 turns depending on how much meter she had. Kaede, on the other hand, needs an expected 200 meter to cap attack down. That's not reasonable; her uplift isn't strong enough to fuel that kind of expenditure, and Lucilius having AoE or multi-target autoattacks rules out her revitalize passive as a source of meter. It also doesn't help that even refreshing debuff stacks once they're up is a chore, since the right one needs to be rolled. In a pinch, it's still sort of usable, but I ended up treating her debuffs as more of a bonus than an essential component.
Compounding those problems is that the rest of her kit doesn't contribute anything valuable, either. Her special buff is nice to have, but being a normal buff really cuts its effectiveness and even if she doesn't need to spend any meter on debuffing, she'd still need to be fed meter to maintain it, which is not worth the effort. Her healing on ougi isn't needed with Andira around (and the healing cap on it is low, anyway). In short, she can't debuff properly, doesn't have any other defensive utility besides some chip healing, and does no damage. It got to the point where the grid Belial's not to flex, it's because I was timing out without it.
While the wings were up, Kaede's debuffs were a bit of a necessary evil; even if they're not great, having them was preferable to no debuffs, and attack down on the body is mostly covered by MC, anyway. During the body phase, they weren't needed at all. Gopherwood is actually where I appreciated having her the most; MC doesn't have the time to max out debuff stacks, so having a supplemental source of those is helpful.
Really, though, even with the understanding that she's a free character, keep her out of your parties unless you're a Hayamin enthusiast or something. Monika isn't exactly a fair comparison since she costs 30k arcapoints, but that's still not from the gacha and she's far better.
no wind ship/reactor
0:00 start
9:23 wings 50%
17:10 wings 0%
24:00 body 25%