New Player - Job Level Boost

[Hasrat]

Question 2 then, if I buy the one for completion of the MSQ, does that unlock all associated duties from Realm Reborn and Heavensward? How long would it take me to level up my job to level 60?

If you're running a tank, and you understand your kit well enough to not have any serious issues and can get through dungeons easy enough, you'd probably get there in a couple weeks at most. Tanks have little to not wait time for getting into dungeons, and are near always in high demand, providing an extra exp boost when you queue into the roulette (set yourself to "Join in Progress" to probably speed things up even more).

The boost does unlock everything MSQ related, so you could literally just sit there spamming roulettes with the occasional break for job quests.