1) Disguising yourself like a ally of your target - i hate those missions, because they dont allow you to be creative. the idea itself is creative, but after all its not us that came up with it, so when we're doing the mission in a disguise all we have to do is walk right in there and kill them. Doesnt allow us to be creative at all.
2) Getting help from others - another annoying type of mission is where you HAVE TO use the assassins/thiefs/mercinaries. eg. the mission in sequence 7 i think it is in ACR, where im killling people, and the assassins come along and take all my kills. If there are kills to be made it should be our choice who does them. the whole idea of being a master assassin, i think, is so that i can do things alone. i dont want help it limits what i can do, and makes missions boring.
3) missions where you have to follow a set path - eg. in AC2, ACB and ACB where you had to find the keys for armour/library. there was no point in those missions, they may as well have made them cut scenes because there is only one way to go you have no choice but to go that way, to get to the destination, whereas in missions such as, leonardo's war machine, they give you the target, and you have to find your own way there, killing who you want, when you want, if you want, in whatever way you want and ALONE! theyre the best type of missions
4) In addition, i just remembered, the apple missions are sooo painful. They are agonisingly tedious and boring