Hi,
They usually start with a contract of limited duration (6 months up to 2 years). To get a permanent contract you have to speak at least 2 of the national languages (FR+NL usually or DE) + English of course.
Starting salary is about 4400€ before tax (approx 2300€ after tax as the taxes are very high in Belgium) under a Belgian contract. You get approx. 9€/block hour and 75€/nightstop. All-inclusive you can expect around 3000€-3500€ after tax/month. Bonded for 2 years if not rated on A320.
Roster is usually 7/3 or 5/2, you can get more off days during the winter season. Unfortunately the rostering system is terrible (start your week with an early flight, then get some late flights and finish with an early is common there). Crews are nice (with some exceptions as in every company) and training is excellent. Hotels are also nice and you can expect some long nightstops (up to 3 nights during the week end which is very nice if you want to visit cities in Europe). Time to command is a big question mark...some guys are sitting for +12 years in the right hand seat waiting for upgrade.
90% of the longhaul destinations are in Africa, some people really like others don't.
You can expect staff travel after 6 months in the company.
A lot of people (including me) left in the last few months. Some captains even left Brussels Airlines to start again as First Officer in other airlines due to poor terms and conditions and a very uncertain future (integration into Eurowings).
So I think it a good company to start a career
Good luck with the assessment !