Don't be such a simpleton. First of all people manipulate other people that is the way it is. You really can't get anywhere in this world if you aren't willing and or able to use and manipulate other people to get where and what you want. Manipulating people doesn't make him a coward it makes him intelligent enough to understand what is necessary to get what he wants. Something you obviously are not since you are a complete tool.
Secondly what Aizen did in SS as he himself said he did so that people wouldn't get in his way and he could move around freely to accomplish his goals it wasn't cowardly, it was ingenious.
Now you have to be a complete fool if you think Aizen ran from Urahara. Tosen was going to kill Urahara but Aizen stopped him. The reason Aizen stopped him is because he realized Urahara was doing research in the same field so he didn't want him killed if in future Urahara could help him achieve his goal, and that is exactly what happened. Aizen would have never have been able to achieve his goal if not for Urahara. Besides its pretty obvious that Aizen was stronger than anyone else there at that time.
You do know that that entire scene on top of the execution grounds makes all of this wrongOriginally Posted by The Archangel