The male lead shouldn't be a prince. He should hide away and quietly build up his strength, training an army. Preferably no female lead. He should be decisive and ruthless, not a bleeding heart.
Jue Juezi, whose IQ was crushed throughout the whole process, was the useless sixth prince at the beginning, and continued to expand his power. In the end, he wakes up to take control of the world and lies drunk in the lap of a beautiful woman. The author's text is very good, and it is not depressing to read. I highly recommend reading it. (Harem + struggle for hegemony + battle of wits + cool writing + useless prince at the beginning)