I do think 1 is a pullet and 2 is a roo. 1 has no red at all. 2 definitely has the most red in the comb and wattles.
3 I am on the fence about. The color is definitely in between 1 and 2... it is red but not as red as the 3rd. The comb is also not as small as the 1st but smaller than the 3rd. He/she was definitely the most skittish. He/she was freaking out about being away from the other 2 and would not sit still. Not that it has anything to do with being one or the other.
At 6-1/2 weeks, should any red in the comb and wattles indicate a roo?