I just spooled my line on a reel, and although the line is fairly even in terms of looking at the reel from above, when I look at the reel from the back, each line wrap looks a bit uneven. Is this OK?

Yes, its not going to be perfect. After you start casting and retrieving, it will become uneven sometimes too.

Why would it become uneven after casting and retrieving? I thought this helps straighten it out?

Why would it become uneven after casting and retrieving? I thought this helps straighten it out?

Thats just the way a baitcaster works. The line guide may have stopped on the right side of the reel while the line finished coming off the left side. When you start to reel it will become uneven. No way to keep it perfect.

It just happens depending on where the line is positioned during the cast, to where the line guide is positioned when you start retrieving. They dont always line up after each cast.