Good ranking. That said, your placement of Brotherhood and Revelations surprises me, especially the former. Very glad to see Unity so high. It deserves that.
Thanks! To be fair, I love them all, but I just really didn't care for the story in Brotherhood. It was cool to see Ezio create his Brotherhood, but Borgia was an eh villain (kills Rodrigo with an apple...lol) and the whole "is Machiavelli a traitor" plot didn't hit for me. It felt like an expansion of 2, not a full game.
Conversely, Revelations had a GREAT story and the connections with Altair and Desmond were perfection. I enjoyed the hook blade, Ezio's relationship with Sofia, and the opening section in Masayaf was bliss.
When thinking about my favorite games in the series, I had to put Unity near the top. The story isn't as good as II or IV, but the gameplay, city, graphics, and traversal are amazing. I've never seen a city with more npcs than Paris, the series got a crouch button for the first time (!!!), and the combat was actually challenging. But on top of it all, the black box assassination missions were easily the best in the series.
Kind of a controversial take, but I didn't enjoy Origins as much as I thought I would. I HATED grinding materials to level up the hidden blade, and the level thresholds for missions really rubbed me the wrong way. I still haven't played the DLC because I don't want to grind levels to be strong enough. It also didn't really set up the assassinations as well as other games. I killed the first target by accident, thinking he was a normal enemy... I enjoyed Rogue a lot, but had to put it lower because the scope just doesn't compare.