The Amaro mount...

[Halivel]

With that requirement, and the 1-2 years of grinding needed to accomplish it. the mount should do FAR more than just run and fly.
It might be worth it if the Amaro could:
1. Fly at up to 100 times as fast as any other mount (with continuously-variable speed.)
2. Fly in ALL zones, including new ones, without the need to quest and collect things.
3. Carry passengers, including a permanent extra retainer, (free).
4. Provide free teleports to any Aetherite.

You highly overestimate leveling speed tbh. I leveled GNB from 60 to 70 in one day, and then few days for leveling until 80 with MSQ and I wasn't really fast. Right now, if you have one class at 80, all other jobs will have 100% exp bonus for 1-70 levels and 50% from 70 to 80. Plus rest bonus, pluc FC/Squadron bonus, plus additional items like earrings if your level is under 70. In fact, you will need about maybe week to level one job if your online is not very high. I'm quite sure we will see first Amaros less than in a month.