Seasoned Modern players are well aware of the delve mechanic and its advantages. Cards like Gurmag Angler and Tasigur, the Golden Fang have been staple choices in many black decks as a result.
Pteramander offers something similar in decks that focus on casting lots of cheap non-creature spells. Think of archetypes built around Delver of Secrets or Young Pyromancer.
Both of these creatures want to be in decks with a great number of instant and sorcery spells. In these decks, you could quickly accelerate to Pteramander as a 5/5 flying creature for only a couple of blue mana.
It also works great with Dark Confidant, which will only do one damage to you when revealing Pteramander.
There is definitely huge potential in this little card.