Thanks for your feedback. I am surprised that that was only a 15 year old plane. It is in rough shape and was not well cleaned or maintained.
As it goes for the takeoff, the plane clearly labored to get off the ground. The long take off can be planned but combined with a prolonged period at low altitude is far from typical. Air traffic doesn't want a commercial plane staying in the small plane zone for an extended period. We were well on our way to the channel before it really started moving into the normal expected altitude. I will leave it to the air traffic controllers and AF to determine whether this is normal for them. For me, I don't want to experience it again.
I use FT to get information about airlines and I was interested to see whether this was typical service for AF (I won't get into a debate with anyone about what I did or did not experience). It is good to see that AF has loyal followers which may mean that my experience was an anomaly.