Thanks for considering CLX.
A lot of your requested information can be found in this thread already.
Income depends on your family status and number of kids.
Expect 6-700 € per month more if you are married.
After 600 hrs on type you move to the SFO scale.
Per diem is not bad and some consider it part of their salary.
Days OFF are 3+1 and 6+1 per 28 day roster period, resp. 9+1.
CLX loves to hire people that are living close to LUX.
At least you should convince them that you intend to move close to LUX.
Many people commute in a range from 200 to 700 km by car, some by plane.
Tiredness depends on the actual trip you are doing. There are busy ones and not so busy ones with more or less night duties and with standard or augmented crew.
This is just about layovers (block to block).
The above samples do not reflect if you are operating and/or positioning or doing a commercial positioning.
In my opinion flying for CLX is less tiring than flying shorthaul nowadays.
But this might not be true for everyone.