The best thing you can do with the AK's, is learn to run them like an AK. They arent an AR, or anything else. Once you figure them out, and they are pretty simple, I think youll find things go much better, and you'll have a better experience.
First and foremost, the stocks are not "to short", as youre often told, and have the same LOP as the M16, M16A1, M14, M1, etc, right around 13". When you shoulder them, you want your cheek weld on the "wrist" right behind the rear trunion, and youre nose at or along the top cover. You dont want your cheek weld on the "comb", like you often see. That will give the impression the stock is to short. When shouldered properly, they will shoulder easily and naturally, and the iron sights line right up as the gun is shouldered and you dont have to go looking for them or really need to align them much.
A couple of things that will make the mag release and selector easier to use is a little file work. The parts are stampings, and usually have sharp edges because of it. Break those sharp edges or points with a jeweler's file, and you can work the levers easily one handed, with little effort, basically just using your middle finger, and with your hand on the grip as you do it.
If you look at how the mags lock in, youll see where you need to hit. It just takes a little too, dont go crazy. Once you do it, the mags should drop free, or with a slight rearward pull/shake.
On the selector, the little dimple on the back, that drags the arc through the finish on the receiver, will benefit by having the "point" flattened a little, and depending on the gun's receiver, there may be a little ledge at the top, that it tends to get hung up on when "on", that youll want to knock off with the file, so it slips by smoothly.
One thing about the mag changes, you want to make sure you get them rocked in properly or youll get to experience one of the worst malfunctions you can have with the AK's. They dont happen often, but you need to know what to do when they do. What happens is, the mag looks like it is seated right, and locks in, but the dimple of the front of the mag is against the mag well, instead of up in the proper place, and the mag is too low for the bolt to strip a round, and its in effect now jammed in the well, and it won't come out by pressing the lever and dumping or pulling it out. The only way I know to get it out, is put the butt on the ground, with the muzzle away from you and kick it out. As I said, they dont happen often, if you use the proper technique seating them, but when they do, youll know it, and you need to know what to do.
The best sight tool Ive found is one that was made by B Square. Last I heard, they quit making them, but if you can find one, maybe on eBay, they are well worth the money. They move the sight barrel in tiny increments and will push the stiffest stuck barrel too. You can also leave it on the gun while you zero (for the windage adjustments), but youll want to take it off for the vertical. They work on the SKS's too.
The cheap "U" shaped ones basically suck, and just make things difficult, especially if the sight barrel is the least bit stuck or frozen. I trashed a couple of them the first time I tried using them and bent them out of shape before they moved the barrel.