Presumably the TRADE Federation and BANKING Clans could outbid them.
Those are some mighty easy principles to espouse at the cost of OTHER people's lives. They were on Naboo like five minutes before they started setting up concentration camps and even driving the submarine Gungans out of their cities and into secret places of refuge. Each one of those "few planets" is an atrocity worse than anything in the whole bloody murderous 20th Century.

And that was not the choice, the choice for Yoda was to let the cream of the Jedi order be slaughtered TODAY on Geonosis while he waited to acquire an army more acceptable to this sort of barracks lawyer nonsense. People who were irreplaceable and who were vital to keeping peace and order in the Republic and preventing it from succumbing to the eventual doom of a militarized state with an army. People who might be the only hope the galaxy had against the Sith Lord moving in the shadows.

Eh, that's presentism talking. That was a pretty big jump, and you've completely overlooked my point that the army was ALREADY in the hands of the Republic, and commissioned by Sidious' henchmen, so it's not like Palpatine would not have been able to take control anyway. The option would be turning it over to the Republic's bureaucrats, to appoint political officers with no real experience to lead them into the slaughterhouse, or take command themselves, ameliorate the abuses and prevent the army from being misused, or becoming an instrument of tyranny. They were already way in over their heads, and it's only with the benefit of hindsight that you see how their actions doomed themselves. Also, Sidious had been working on this plan a long time, presumably as the consummation of a long-term Sith strategy. He almost certainly had other plans to nudge the Jedi into the much if they held themselves aloof from the fighting. They doomed themselves however many generations previously when they took up the cause of the Republic in the first place, and became an institution of the state.
What difference does emotion make? Possession or application of emotions is not good or bad. Nor do emotions have anything to do with free will. If they have no will, they are basically biological machines or robots, and morally no different than a gun.
IDK what your point is here, if the clones are people, they are EXACTLY like Janissaries, because they basically ARE Janissaries.

As far as slave soldiers go, all of Europe used them in just about every war since 1789, and the US in every war of the 20th Century until we abolished military conscription. Clone troopers are no different than draftees, they just have a couple of superfluous steps removed between being born in the control of the enslaving power and the formalization of their compulsion to fight.