Personally, if it was a choice between a neutered AR and a Mini-14, I would choose the Mini in a heartbeat. I don't like messing with the functioning of a weapon as it was designed.
While a well built AR may have higher durability than a Mini-14 in high volume, rapid shooting situations like a carbine class, just how many rounds at a time and how quickly do you think you can shoot with 10 round mags and a bullet button?
The sight line of the AR is high because the stock is straight. Unless there is something wrong with your face (or you are doing it completely wrong), when you rest your cheek on the stock, your eye should line up with the sights.
The stock is straight to reduce the upward climb during full auto fire. With conventional stocks that have drop, a portion of the force coming back into your shoulder will also torque the rifle upwards. This is really only noticeable in full auto fire though.
If you lower the sights on the AR, like other rifles that have drop in their stocks, you won't be able to see through the sights.
If you are going to want to add lights/lasers/optics, the AR is going to be easier to do this on, if you are willing to deal with a bullet button.
I have no experience with AKs in .223. I have heard they aren't as reliable and every manufacturer uses different magazines, but I don't have personal knowledge of that.
(Of course, the best thing to do is move to a free state