Well.... I can name a few.
Back on topic, people are right in saying that compared with FD, FB is a really watered down programme.
On the other hand, with access to AF flights now, the earning and burning opportunities have increased tremendously -> what would we be saying if we had all those miles but with current loadfactors of KL were not able to use them?
Agree with Jouy that open miles can work out well, although sometimes I get the feeling that they close D-class availability deliberately to get people to use open miles.
In the past it was really easy to upgrade on KL, even from V-class. And that is quite a loss although the "pay a fee to B-class and then use miles to C cabin" on KL is quite good (cannot do this for V-class).
In terms of lounge access, we were spoilt in the past with access to all KL lounges irrespective of carrier flown. But now with some very good AF lounges at many airports I am quite happy (and otherwise use Priority Pass).
And, in fairness, the award calendar feature seems to work pretty well.