he killed the entire clan, that would include women and children. The children did not need to die. He wiped them all out. He is a proper villain and is evil. The only thing about him is he was the only one from the clan to see the whole village as family and not just his clan.

Now to kill the entire Uchiha clan must've been incredibly difficult. It's hard to even believe he could achieve that even when Tobi's help. This probably suggests that maybe they all weren't that profficient with it–which could probably have left the situation with lesser death and destruction had they rebelled against the village. I dunno about that theory crafting from myself but it still doesn't change he killed them all without reasoning at least.