@zalem: Not at all. Sheryl is the one who always gives Alto's paper airplanes flight.
The very first scene that we have of Alto shows him making a giant paper airplane out of a Sheryl poster. He then launches it into the air and soars up into the heavens after it. In episode five, Alto launches his paper airplane only after Sheryl gives him insight into why he feels so driven to fly. Finally, in episode nine, when Alto's paper airplane hits the wall, metaphorically portraying the cage of obligations that both Alto's family and Ranka had imposed on him as 'presents', Sheryl was the one who gifted him with the freedom to fly freely. It's a bit lengthy for a name, but it's still much more appropriate to Alto x Sheryl.
That being said, the best choices will probably be short as well as symbolic.
Some other options could be 'Earrings Faction' or 'My Girlfriend is a Pilot' (MGIAP?)
@lone_wolf: Royal Couple? Royal Flush?
'Imperial' makes me think of an emperor or empress, and we have neither here. But I can see why crisis would like the idea of an Imperial Shipping Fleet.