@Dynamicd,
First , you should find out which company you want to join according to what you are looking for ( big aircraft long haul operation , medium aircraft low cost operation , looking for quick command or not , lifestyle you are looking for etc... )
Then when you choice is made , do what is needed to get hired by this company and then if you fail to join try your next choice...
There is nothing more different than Flydubai and Emirates so think carefully before deciding.
There is no reason why you should not be able to join QR or EY after Flydubai but it is true that for the time being pilots from Flydubai trying to join Emirates have been told NO because there is an agreement between the 2 companies as they belong to the same government.
It seems that after 3 years in Flydubai the ban will be lifted and you should be able to join Emirates... Wait and see.
But again , if your goal is to join Emirates go right away to Emirates.Why would you want to loose 3 years of seniority in Flydubai ?