Who is the best candidate for Hone Fliers?

Your Camilla for sure, that way she can provide that +6 atk/spd to potentially all 3 of your offensive units.

As a general rule, you want to give hone buffs to your tanks, and fortify to offensive units assuming a standard hone×2 + fortify×2.

Only exception is that I sometimes run bladehorses with hones that way my Leo and Olwen can buff each other in a pinch when separated from the main team (S Supported as well). So if you were running Nowi alongside Summer Camilla/Corrin that would have been a different option.