I'd say increasing the cost should solve more problems than anything.
Another strategy could be to phrase the card's effect in the following manner:
"Target card is returned to it's owners hand. Deal 3 direct damage instead if it's owner has a shield in play."
The upgraded would use the same phrasing but a cheaper play cost. The theory behind this version is that when you hide behind a shield how much does a gust or gale really do? Maybe a few scrapes? Plus, with Shockwave already being a form of direct spell damage,
Air could do quite a number with just spells!
EDIT: Also, you probably don't want to be destroying cards if someone's hand is full. This card should do nothing if the hand is full, or 3 direct damage if a shield is in play, should you choose to accept this version.