When recovering as Ike you have 3 options.
First, if knocked at a high angle, use Quick Draw and expect to dash into a safe position, don't use it for the ledge more often than not, but to get to the center of the stage.
In many other cases, you want to get below the edge and Aether. We all know that everyone likes to gimp out Ike's recovery, so this is where your mindgames and skill need to show the best. There are times when you want to Aether as soon as possible, so that you can begin the SAF of the attack and not get gimped. If you have a few moments to hold (which you often do since Aether as so much vertical distance) wait before using Aether, and if the foe jumps down too soon you can throw the sword into him. Also, if you make Ike use Aether in the opposite direction (which would mean you would catch the edge with your back) you can on occasion hit the opponent in cases where you would normally not.
Finally, in a lot of situations you can afford to air dodge and maybe even Nair one good time and then Aether to the ledge, which you need to be ready to do on a hasty opponent.
The last option is suicide, if the opponent is at a high % and tries to jump down to ensure your death, hit him with an uncharged eruption. Eruption kills a lot of crap at the right %, even without a hint of a charge. If you can save your second jump, then use it with an air dodge and follow it with a Dair to punish the opponent, then try to recover. Just remember, if you hit an opponent at a weird angle when he hits you at the same time, you can move at an unexpected angle, often killing the opponent but not being knocked back so far you can't recover.