Ya, I'd say you have it down. I don't see one there I don't like. To my eye you did just the right proportions on the ones that have the three pieces of a cartridge. Great pens.
I think they all look great! The only thing that jumps out at me is the serrations on the bullet.Personally I don't care for that look so when I get a bullet like that I'll seat it a little deeper to hide the lines. Keep up the good work![8D]
Your pens look very nice. I don't think there's anything about them to "tear apart". Some of the proportions are not to my taste, but that's simply a matter of personal preference. Myself, I like the bit of cannelure you've left exposed on the bullets. That is where the manufacturer intended the bullets to be seated, so I think it makes the cartridges look authentic.