Apart from what Canvas said,
You can get loads of momentum from U-air mid attack. The hitbox on the side of it is useful for this. Apart from this, though, none of sheiks moves are particularly great for recovery from the ledge.
A couple of things I used to do back in the day (that still work)
Hit away from the ledge and do a transformation Jump. Unless you're on WiFi you can make it back as Zelda ON to the stage using her UpB. Obvious risk, but it hasn't failed me too much.
Another thing is ledgehop > Chain. I have chainjacketed it once that way. It was cool, but not reliable. A simple chainlock will work here depending on who you're fighting and where they're standing. These things are all very situational. You know your opponents mannerisms better than we do, so use that to your advantage. Be "intuitive."