.zerocool.,
You come off sounding like a 16-year old trying to give everybody advice based on your custom airsoft gun. I don't know where you are getting your knowledge, so what is your experience with the AR? Until you prove otherwise, you give the impression of a mall-ninja poser based on what I've seen you post in other threads.
Your logic and suggestions are flawed in more than one area.
How do you figure the carbine buffer tube is weak due to leverage? How do you figure NC Star is good to go over an ACOG or Aimpoint? NC Star is JUNK. Not even worth putting on an airsoft gun. You get what you pay for with optics. The KNS anti-rotation pins are unnecessary on any properly built AR.
The Accu-wedge is not recommended by serious users in any rifle used in any serious capacity. They have been known to come apart in the lower. A sloppy fit between upper and lower is not going to affect accuracy, your barrel and sights are all solidly affixed to each other on the upper.
The AR as a base is filled with problems. From pin walking / rotation, to the excessive need to clean. I for one have had an AR jam many a times. Stocks break/shear off, castle nuts loosen, it takes a 3 handed operation (speaking of which, there is another part I'll add to the list).
This is so absurd I'm not even going there. Do your homework for mil-spec AR-15s. I can trust a stock Colt 6920 with my life. A 6920 with good ammo and good mags will run circles around your AR-57. You will not have a problem buying quality, such as a BCM or Colt AR-15. There are qualities and specifications about these rifles that Bushmaster, DPMS, RRA, and many others cannot meet at their price point and that is why there are serious, hard-use AR-15s and then there are recreational guns.
Also, no matter the quality or cost, the AR is still prone to all the same issues
Yes, quality and cost matters. There is a reason Colt, LMT, Noveske, KAC, and a few others are considered good-to-go when it counts versus brands like Bushmaster. If quality and cost didn't matter nobody would shell out $2K for a KAC or a Noveske. You said a 500-dollar Bushmaster works the same so I guess I shouldn't waste my money on a KAC SR-15E3.
Through my experience shooting the AR as a civilian and in the military I have found the best add-ons are:
-Training
-Quality magazines
-Two-point sling
-Sturdy weapon light
-Quality trigger
-Quality optic such as Aimpoint or ACOG (not NC Star, keep that crap in China).
I'm not gonna say which ones somebody should buy because it's all based on preference and as long as you buy quality and you learn how to use it it will make you more effective. The training helps big time in learning how to apply the fundamentals as well as make the most of your add-ons. I use a Geissele SSA trigger, Lancer mags, an ACOG, and a SureFire Scout Light. They work for me. The next guy might use PMags and an Aimpoint. The next guy might have just iron sights and a sling but has attended over a dozen carbine classes. It's not all about hardware.
Based on my experience with the AR-15/M4/M16, I haven't seen the issues that the OP says are normal with the AR family. He is mostly talking out of his rear end. You mention post counts on more than one occasion. I don't even look at other people's post count, I read what they have to say and prefer useful and intelligent information. You are new here. Read more and post less.