How to convert Pit/Dark Pit's drag-down nair into another hit

Solution 1:

The non-final hits of Pit's neutral aerial deal 0.7% damage with 100 knockback scaling, and the parts that hit downwards have 30 fixed knockback (source). This means it'll do somewhere in the range of 37.06-45.65 knockback and therefore 13-17 hitstun (the variance is based on weight).

However, Pit's neutral aerial has a landing lag of 14, and his jab and grab don't hit until 5 and 6 respectively. So in the absolute best-case scenario, where you land the frame after you hit with the neutral aerial, the opponent can begin their next action 2 frames before your attack or grab comes out. Since perfection isn't guaranteed, the looping hits happen every 3 frames, and the opponent can land before you do, this'll get even worse.

So falling n-air with Pit isn't that followupable unless you're in a position where you will land significantly earlier than your opponent (and they still need to land before their aerial action comes out).