Personally, this bird is too young to determine how he might turn out. But it's good that you are looking now and you can keep an eye on things and watch his development. But don't get too hasty yet (on liking him or not liking him) because they don't really fill in until they hit about 8 months or more. I had a male last year that looked like a pullet up until he was 6 months old, and then he started getting in streamers and filling out. Even at that, he continued to fill out at a year of age. SO much so-- that he wound up too large! (too heavy) Because I didn't wait to make sure how he was going to turn out (I just saw that he was very typey and looked great, I started using him). Now I have a lot of off spring that I'm worried are going to be too big--I was too hasty and I won't make that mistake again. Your boy doesn't have his crest in yet, and his wings are really immature-- he is missing some primaries. They may not be actually missing... they could just be taking their time coming in, but do keep an eye on that. Make sure they do come in. Another thought on wing carriage, unfortunately, my boys tend to drop their wings when they hit maturity. I have 'before' and 'after' photos of this happening even with my boys this year-- very frustrating. I've heard so many people say this happens with their boys too. I think since he's 3 months old, it's just too early to tell how well he is going to fill out quite yet. I do like his comb--it's nice and dark and has a great shape to it.

The right foot (it's actually his left) doesn't have good separation on those extra toes, but that could be worked around with a hen that has better feet and cull hard. And BTW, your 4 year old did a fantastic job taking pictures!! I don't know if anyone else feels this way-- but personally, I think boys are harder to critique. You just have to wait much longer to determine how they are going to fill in (up to a year old or more!). Pullets are so much easier, they still may continue to fill in, but you have a much better idea of what you have before they get too old.
Maybe someone else will chime in with their thoughts on this. Growing out cockerels is a fun topic!