Ledian was always a personal favorite of mine, despite its terrible stats. I can see the focus you've went for with this moveset: A ledian with good sweeping attacks that passively aid in its Special sweeping abilities, and has included good type coverage. I must say, it's a good moveset, but is not a very good choice on a Pokemon like Ledian. Ledian is not the kind of fighter who can just sweep and cut through opponents.
Ledian is a Pokemon that you have to be very patient with, and they are mainly used as supporters or dual-screeners.
Bug Buzz is the only attack you'll want on Ledian. Good power, like you said, and it's just really reliable. With base 55 Special Attack, I doubt you'll be doing much, but that's okay.
Swift and Ominous Wind? Great attacks, but you need support for this fragile ladybird. Slap the dual-screens on 'em. Reflect and Light Screen will help immensely for Ledian, along with supporting your whole team. Ledian already has acceptable Special Defense, so if you want to keep Ominous Wind or Swift over Lights creen, then that's fine. Get Reflect on it though, to help with its meager Base 50 Defense.
Lastly, you want that rare instant recovery that few Pokemon can learn: Roost. Roost heals half of your HP, and takes away the Flying-type from Ledian for the turn you use it, which can be a great Defensive maneuver! If you don't have access to Roost, then Baton Pass is a good alternative, so you can instantly switch in a stronger pokemon after you put your walls up, without the risk of being hit by pursuit.
This is just one opinion, but with this moveset, I ended up with a lv. 61 Ledian that could survive (even against the fated Salamence), and hit the opponent back fairly well with Bug Buzz (Of course, I'm not talking about that Salamence anymore, haha).
Remember: Ledian makes love, not war. =P