Thank you for your reply Dagthul and sry for that it took so long to reply, but I have been busy with work, and a little bit in wow.
When I said that I had more rage than other warriors, actually I was comparing myself to a Fury warr (top DPS in my group at the time). I guess I shouldn't do that anymore.
I didn't knew WeekAuras before. I have seen it in some videos but didn't know it was it. I have installed it, watched some videos and made some Auras of my own (that's why it took so long for me to write back).
http://postimg.org/image/gtzza716r/There aren't that many but I am still getting used to them and improving them.
Currently I am tracking:
-banners and rallying cry - if someone has casted them or if I have them on CD (in the past I would have looked at the buff bar and try to find if they are active)
-rage amount
-shield barrier duration and absorb amount
-if shield slam and revenge are off CD (those 2 are a little buggy because they do pop up when the spell is ready but they get out only after x sec. I still need to find a way to make them disappear when I cast the spell)
And I am planning on adding auras to track Weakened Blows and Sunder Armor on target and if I am enraged or not so I can use Berserker Rage.
When I was saying that I spamming devastate, I was saying that I was pressing it really fast (one/twice a sec), even though it was on CD, to proc Sword and Board and get an extra Shield Slam. My mistake was that I was casting Shield Slam and Revenge only when they proc'ed (because a shiny contour appeared and was easy to spot). I have understood everything you wrote and I realize that I was doing it really wrong. In those 6 sec that it takes for shield slam to reset I will prioritize casting revenge, storm bot, Demoralizing shout, Thunder Clap, Berserker Rage (if not already enraged) and at the end Devastate.
To get rid of the habit of constantly pressing the Devastate button I have rearranged my spells and added new key binds to the abilities that I was either using them improperly, not often enough or wasting time by clicking them.