You should hop over the Prequel Radical Redux Ideas thread, Pan! I know versions of your idea have been suggested before.
Basically, the Clones aren’t a mystery, and Obi-Wan just goes to inspect them in AOTC instead of just discovering them.
You would have to change a few things, since Padmé was voting against the creation of a Grand Army of the Republic. But if the army is already being created, you would need to make it where she is trying to do something else. Maybe she is just a leading voice in trying to find a diplomatic solution to the Republic/Seperatist arms race?
You also would have to figure out what Obi-Wan will do for the majority of AOTC, since you would have to rework the mystery plot.
Maybe the general structure of the film could remain the same, but alter the Kamino scenes so the Clone army isn’t a mystery to him. Basically, the death of Zam/the saber dart could lead him to Kamino, where he finds out that the bounty hunter he is after is actually the template for the Clone Army. Maybe the connection between the Clone Army, Jango and Dooku would be less suspicious since the Clone Army isn’t a secret.
I’d definitely suggest continuing this conversation to the Prequel Radical Redux Ideas thread. https://originaltrilogy.com/topic/The-Prequel-Radical-Redux-Ideas-Thread/id/9911/page/1
There are general idea threads for all three trilogies, but maybe we should make a general Skywalker Saga Ideas thread too!