@pinkflaps
It depends what you are looking for ?
In Etihad and Qatar Airways you will have the opportunity to fly long haul...
In Flydubai there are only B737 so no long haul BUT you will be home every day , no jet lag .
Also Flydubai is a low cost company while the 2 other ones are flag carrier so the way you will be treated will not be the same ( salary , medical insurance , loss of license , school allowances etc are better than in Flydubai...
So it is really up to you to see what is more important for you ?