I think there are two points I can extract about Liu Bei and Cao Cao :
1. In the discussion, it's pretty obvious that Cao Cao was trying to gain Liu Bei's heart not as his follower but as his friends and as equal partner in restoring the Han, why ?
Well, if Cao Cao considered as a rival, I don't think he would give Liu Bei an army when he asked one. Plus when he gave this army, he did it without any doubt. Meng De just gave Liu Bei the army and sent him away to fight Yuan Shu without thinking. Surely a person like Cao Cao wouldn't give a large army to a person like Liu Bei if he didn't trust him as a friend.
2. Let me quote :
Liu Bei replied, "I have been a bird in a cage, a fish in a net. This is like the fish regaining the open sea and the bird soaring into the blue sky. I suffered much from the confinement."
IMHO, this lines are very good sign on how ambitious Liu Bei was. It was his desire to start his own kingdom. Surely not the person we all know who used tears as his weapon.
What do you think ?