Need help in choosing job :)

[ItMe]

But i can't even imagine how to level another one after completing MSQ..It will take months ;D

Nah, just a couple weeks.
Hitting the leveling roulette consistently alone does wonders for your EXP.

Here are two videos that should tell you all you need to know about your levelling options and how to do so efficiently:

https://youtu.be/3IOdiwABIJk

https://youtu.be/uK5Oj3nPgMU