Well, With Sasuke I have liked his character and disliked him depending on the situation. The only character I can claim to hate in Naruto is Obito for being an irritating none entity and for the ruthless murder of the charming character called Tobi (who actually had a personality)
First we do have to remember that Sasuke did not know anything about why Itachi killed everybody until somebody told him about it (quite a while after the event)
Therefor this revelation crushed his previous understanding of his brother as a murdering lunatic (which I think Itachi still was anyway… he did kill his parents, his extended family, friends and his entire community after all. No matter for what reasons anybody who would do all that is still rather deranged)
So from shifting his blame from his brother who he had just killed (or assisted in his suicide) he was informed by Mr. unknown Uchiha that a Konoha conspiracy was responsible for his brother’s actions (well, I still think Itachi was responsible for those actions no matter who gave the order, his choice)
Now, even if the list of people responsible for the order can be limited to a few names it was the village structure which issued those orders and Itachi’s dedication to that cause which was responsible for the murder. Sasuke could have been enraged at his brother’s dedication to the village and therefore hated the village as strongly he hated Itachi. In effect the vengeance he had delivered against Itachi upon the implication of Konoha in the act could not be left to rest in peace and instead shifted fully to ending what had become a matter unfinished.
I would criticize Sasuke for so readily “forgiving” Itachi at this point but I think his hatred to the village structure which had cost him his family is entirely justified.
I think Sasuke abandoned his plans of vengeance far to easily after his talk with the Hokage. I am considering if Sasuke may have not changed his mind and has ether decided to remove the immediate threat (Obito and Madara who would take away his opportunity to avenge himself against the leaf) and then attack the leaf. Or if he has focused his vendetta at the village’s high command and desires the position of Hokage so that he may purge them out (the elders, black ops and all those chaps)
I liked Sasuke’s character especially during his argument with Naruto before leaving the village and his self conflict over the choice of staying or leaving. Since then however I have felt that character’s personality has been influenced too heavily by the needs of the plot then his character development. What I mean is that many decisions Sasuke has taken seem forced, unreal. Some of them have been legitimate although not so thoroughly worked out but some such as the most recent return to the “light side” does feel forced. I do hope there is more to this decision then meets the eye however I am afraid to say I do not have enough faith in Kishi to make such a plot twist.
Sasuke cannot be expected to carry out actions just because his big brother told him so, he is his own person. I think disliking Sasuke just because of his naughty actions is a denial of his history, any one after being though what he has been though would have some… problems.
In some way’s Sasuke’s life is even more traumatic then Gara’s and look what a pleasant little runt Gara was when he was a kid!