The Great Sui of the Eastern Lands

If you're going to write mythology, then write mythology. Stop inserting your own opinions. When did Su Dingfang become a foreigner?

An emperor cannot rely solely on intrigue and scheming; he must possess grandeur and magnanimity, and command the overwhelming power of the people. Petty-mindedness is insufficient for his ambitions.

The abstract logic is too weak. The idea that Yang Guang was a lonely ruler came about later; your writing about his past makes him sound like an idiot.

The protagonist only starts thinking about solving problems after they arise. Seriously, since the protagonist is a transmigrator and already knows Yang Liang is going to rebel, why doesn't he prepare in advance or even solve the problems directly? It's ridiculous to wait until the rebellion actually happens before addressing them.

More than thirty chapters already, and I've read nothing.

The flaws don't detract from the overall merit. Write well! The minor flaw is the part about the prison; the protagonist sneaks in twice without being detected. It feels like the prison is a highly secure system, and a mole wouldn't have the ability to deceive everyone.

A being above all others should hopefully avoid too many conspiracies and schemes. One force can overcome all obstacles; focus on development.

The main character is the emperor, and he's still investigating.

There were no eunuchs guarding the place where the emperor's body lay in state, and no guards at the gate. When the emperor traveled, there were no eunuchs or palace maids accompanying him, nor were there any guards protecting him. If there were sounds of fighting in the palace, no one would come to investigate. One might think that an ordinary person was exploring an abandoned house. Watch more historical dramas; the emperor in the palace is the real deal.

It feels awkward; it's neither historical nor mythological, and there's also this abstract concept of national destiny.