I think it rather depends on the type of flying. Various jetpacks etc. work slightly different. Creative style flight however have previously benefited from most things that increase run speed.Any way to boost flying spped in survival? Like an enchantment or special pants or something? Custom 1.12 pack with all the cliches. IIRC, run speed enchants like on dark steel legs does not affect flying speed, right? What about draconic evolution?
Btw. am I remembering wrong, or did there use to be a Haste enchant you could put on boots for increased run speed(and thereby faster flight)? I can only find reference to Haste being mining speed. Was it a mod that added that or?