A 5-2-5-4 pattern is a very acceptable working pattern. A lot of major airlines use a 6-3 or 5-3 sequence. This is absolutly normal for a short haul operation.
The problem is Dani that you are also comparing apples with oranges by comparing EZY to a major.
The issue is that EZY likes to present itself to the outside world as a ´happy family´ and a career airline (like BA and Virgin) but that nobody will last an entire career due to fatigue.
Major (despite using a simular 5-3 or 6-3 roster) do
not constantly use their flight crew to the maximum, where as EZY have no problem scheduling you with minimum rest and maximum flight duties/block hours month after month.