I have flown extensively on AC this year and really find the seats on the Rouge flights terrible for me. I have long legs and am 5'10. My knees jam into the seat in front of me, and I can feel every movement of the person in front of me. I suspect they can also feel my knees. My partner is 5'9 without such long legs and finds it fine. Saying that, for a quick flight to Orlando from Toronto I will put up with it for a cheap flight, or upgrade to business if it's not too bad in price, or my booking class allows my Altitude upgrade.
However, I quite like the service on AC. We have rarely had a delayed flight, and when it did happen due to a mechanical issue, we were in the air in less than 90 minutes. They have yet to lose our bags. The food is mediocre at best - I recommend getting something tasty at the airport and carrying it on. I even have a sealable mug and get a cup of coffee at SB and it stays hot throughout the flight.
We've only had one bad experience with AC where we upgraded seats (paid) and my DH got a standby seat - they were sold out of the premium economy class seats they just accepted the upgrade amount for! What made it problematic was they wouldn't refund our 'upgrade' and put us back in our chosen seats which were together, and insisted I would be seated in the lone PE seat - sandwiched beside strangers with my 8 week old baby! Dh would be seated somewhere on the plane. I wasn't comfortable with that as a nursing mom and as someone who would need a little help with the baby. It DID get sorted out at the airport but I was furious. It was only rectified because someone else didn't show up and they moved us around - at the gate while everyone was boarding. Otherwise we would have been stuck.