dmina, as far as I can see, and I'm just a beginner, but yes they all look female to me.
I know that a lot of people keep Idolos together, and cannibalism never happens until it does.
It's always a possibility, and as valuable as these are I wouldn't risk it. Usually the largest danger comes when they are not all of the same instar and the big guys eat the little guys. They've also been known to attack another housemate while it's molting.
Is that second photo the ceiling? If so, then the general idea looks about right. But as Danny said you'll need something quite a bit taller for the maturing molt. My enclosure is 12" vertically, and with a 2" plastic tub at the bottom filled with wet foam to keep humidity up plus the sticks coming down from the ceiling, there's only about 9" of vertical space. Look again at the photo of her hanging from her exuia in my enclosure, first page of this post ... not a lot of room to spare, her soft, bloated body was enormous!!
Anyway, 1000% better than what you had before!
Well done!