You'll find that almost everyone is flying less over the winter than the summer. The contracts on offer for experienced FOs at the likes of Thomson and Jet 2 are along the lines of 70%/80% initially with time off over the winter.
This is a seasonal industry, and those expecting 90h/month all year round anywhere are barking up the wrong tree. The difference between the places I have mentioned above and FR and EZY are the contract - the EZY Flexi types and the BRK/Storm contractors at FR only get paid when they fly, whereas Jet2 and Thomson will give you a reduced basic over the winter.
The grass is always greener wherever you choose to go. Anyone suggesting that airlines are organised enough to divvy up the hours according to pay rates though has little inside experience of airline rostering and how haphazard it can be.