Too many questions....
QR is looking to buy a regional jet. They took options on the new C-series. However nobody knows if this is just a strategic move to block a production line ( a well practiced move in the middle east), to put them in the leasing company or to operate them themselves!
The end of service benefit is described in the Qatari labour law and thus is a legal requirement to be given to all skilled laborers in this country.
It is three weeks of your last basic salary, per year of service for the first 5 years. For year 6-10 it is 4 weeks, above 10 (hahaha) it becomes 5 weeks
737NG to 777 is possible and depends on company requirements
Long term .....well euhhh????