There's a robust discussion ongoing about whether BD can make a hubbing strategy (ala KLM->AMS and AF->CDG) profitable.
The big weakness is that their fleet consists of either ERJs or 319s. So either very small or a bit too big. "Too small" drives crazy fares to maintain yields, "too big" means finding (stealing) volume in the market that may not be there.
The Avros are on their way out generally - LH, LX are moving off them, and I should imagine SN will be too. They're quite thirsty for what they do.
Unfortunately, I can match your experience of fares, but counter it with examples of being one of 12 people on the BRS-BRU mid-morning flight.