There is the possibility to choose for return flights but it depends on seniority and availability. They adjust the frequency of the flights and add destinations very often making the life of each crew planner a real nightmare.
In some trips, you stay out for only 1 day but some you simply stay 3/4 nights away from home. I rather have these 3 days trip, so I don't have to care about how I'm going to get to the airport or home.
We have lots of red eye flights. Our planes are average 14 hours a day on the air. I had many times my sign on at 23:00lt, next day 03:00lt and the following day 01:00lt. At the end of the trip you're a mess.
gr