In both the manga and the 2nd anime (FMA Brotherhood) homunculi are willingly created. As far as I understand it, Father was created (or rather summoned from the other side of the door?) back at Xerxis before using the entire city to create a powerful philosopher's stone for himself and van Hohenheim.
Some time passed by and father started creating other homunculi, each named after and behaving according to a deadly sin. They are fueled by parts of Father's stone and are powerful subordinates, but neither Greed nor Sloth nor Gluttony use their power to any mentionable extent for Father's benefit.
It is commented by van Hohenheim (and apparently the commonly excepted "truth" as seen in this post) that Father wanted to get rid of these "human" weaknesses. But that obviously didn't work: He still is immensely proud, so he sits alone in the center of the state, never standing up, making subordinates and machines do everything for him, thinking of himself as the best and most powerful being on earth and working towards becoming a "perfect being"; He is greedy, so even though he has a powerful philosopher's stone and can create others from criminals and war casualties, he creates a stone way stronger than his old one has ever been and uses its power to enslave god and steal his/her/their/its power.
And he would have been successful if his underlings had used their powers to their whole extent instead of being too lazy, dumb, or greedy to do so. Van Hohenheim barely completed the inversion circle in time, and with faster digging at Sloth's end and Greed/ Gluttony going on a rampage to enforce the needed bloodshed, Father would have won. (Sure he still needed the sacrifices but as we see in the show, he can somehow make someone a sacrifice by force or he could have just ordered state alchemists to do things that made them become sacrifices. And that's not even the point.)
Is there another reason that I overlooked in the anime or that has been given in the manga why he created his "children" the way he did? Or a reference on why the plan of getting rid of these character flaws did actually work but just not entirely?