Pros: Honorable and loyal to the emperor. Even though he became a regular vassal of Wei, he never displayed any unreasonably ambitious traits.
Yes, in history Xu Huang was a very respectful and effective general. Though he defected to Wei, he physically betrayed no one. All he did was try to persuade his fellow officer Yang Feng to join, and I don't believe Huang was the one who told Cao that Feng was going to snatch back the emperor (I believe Cao saw through it himself?)
From then on, Xu Huang took part in every major campaign Cao established and he performed well in ALL of them. One that really amazed me was when the campaign against Yuan Shao. Those who were defending Yiyang surrendered at first but changed their mind.
Xu Huang seeing through this, knew the enemy had doubts so he wrote a letter of persuasion and fired it into the city on an arrow. The city was won over and he conquered it without any bloodshed.
Cons: Maybe sees expediency as better than purity, as he was fighting for Wei long after the emperor was well subverted.
Well I mean under the circumstances he was in where Cao personally went to Luo Yang to escort the emporer to Xu Chang, what could he have done? He served under Yang Feng yes and was loyal, but what was he supposed to do when Feng abandoned Li Jue becoming independant?
Would he want to go through all that hassle or would he just want to join an established and known power, in this case Cao Cao? Though Feng did fight Cao for power, he lost. So Xu's best choice was to join Cao Cao.
Also, perhaps he died because he was unwilling to take initiative and took a straightforward attack, resulting in death by arrow.
Wait, when Cao Rui took over, he sent Xu Huang to defend Xiangyang against Wu invasion. He died of SICKNESS the same year, ohh - you're talking ROTK, that is why.
-Mo
"Empty your mind, be formless. Shapeless, like water." r.i.p legend...
Bruce Lee