I think we can all agree that Conquest is the best of the three and the only redeemable part of the game as a whole. Even if it's still just okay.
Nope, the only reason Conquest isn't my least favourite of the three is because Revelation is just such a rushed and unpolished mess. If they put literally any more time into making Revelation's gimmicks actually work, it'd probably be my favourite of the three.
Conquest for me has overall the less interesting cast (I enjoyed Birthright's cast more simply because after Awakening I was tired of anime trope types who ram their single defining trait down your throat every time they appear, even if Conquest gave us Forrest), its difficulty curve is a complete mess (being the more difficult of the two doesn't excuse this), and towards the end I was just exhausted of the game and was basically phoning it in because I wanted it to end, where I didn't have that experience with Birthright. It's also not free of dumb gimmicks like the Kitsune map, and the "varied map objectives" and stuff they tried to sell in pre-release didn't amount to anything either.
Birthright was pretty eh too, but at least it felt somewhat cohesive and like it had actual effort put into it. It feels like in terms of time and effort on the part of the developers, Birthright got the most attention, followed by Conquest, while Revelation was sort of slapped together in overtime.