I would be interested to know why you are concentrating on the low cost Airlines.
I work for the National Dutch carrier cityhopper,The cap371 and the new proposed european FTL is much more restrictive than our FTL.
We are legally allowed to work a 16 hour day,Reduced rest is as little as 7.5 hours.
The flight safety department a few years back produced a graph to demonstrate how detrimental the different types of FTL were. KLM was by far the most challenging