I said nothing about game progression on its own. I said that crafting does not in any way keep up with gamestage progression for me. And if you read the forum, you'll see a variety of experiences. For some people, crafting outpaces gamestage. For others, it's far lower than gamestage. And for others, it's just about right. There are many factors at play there, including RNG, perks chosen (including how many different perks are chosen as too many will reduce the rate at which certain perked magazines drop), how much looting you do compared to other gamestage progression like mining, and more.
I don't use bows so maybe they don't show the circle the way firearms do. But they work the same way. The circle will reduce the longer you aim until it reaches the minimum radius. That usually only takes a couple seconds, though I haven't actually timed it and am just estimating. Even then, the area where a shot can go is larger than the crosshair itself and it is placed randomly anywhere within that circle. When aiming at a head that is more than around a few meters away, this circle area is going to be larger than the head, allowing for shots to occasionally go wide. The further they are, the greater the chance of that. And if you shoot immediately instead of aiming, you have an even larger circle so will have a greater chance of missing. Now, there is what seems to be a bug where shooting a zombie that is right next to you might not hit them and it is assumed by players that it's caused by the weapon being past the collision hitbox, though I don't know if that's been confirmed. The basic wooden bow will have a far greater chance to miss than a better bow, which makes sense. I don't know if arrow type matters as well but I don't believe so.
As far as difference between guns and bows, I think the only difference is no drop for guns. That and there is of course different effective ranges and maximum ranges. So I don't know what might cause these misses for you.