I think when Aizen gets free or if he is free then first thing first he will stretch his legs, he's been sitting in that chair for about two years now. Now as for the question of whether he still wants to sit in heaven, think of the reason why he wanted to do so in the first place. Aizen said to Urahara before he was sealed “How can you, who posses such great intellect, allow yourself to be ruled by a thing like that?” So what we can take from that is something is ruling over the characters in Bleach and Aizen doesn't like the way it is ruling so he wants to rule instead but because he is an ******* no one wants him to rule over them.
So yeah I think he will keep trying to stand in heaven or sit on the throne of heaven and change the way things operate, regarding souls, in the Bleach universe. Aizen doesn't seem like the kind of guy to just give up after one try. He'll find a way to be a **** to everyone.