From your list and statements it looks like you are looking for precision first and accuracy standard often lies within the shooters skill, ammo selection and the shooters idea of what is acceptable. What follows is not 100% accurate to every single barrel or every single rifle as there can be variances from barrel to barrel and rifle to rifle.
In general, pencil or the lightweight profile barrels are not as accurate once the barrel gets heated up. There tends to be a point of impact shift and group sizes generally increase. There are 2 schools of thought on this in that generally in a precision rifle, rate of fire tends to be slower, definitely at KKHD on the rifle side, the rate of fire will be slower if you are following the rules. Because of the slower rate of fire the barrel will not heat as quickly. Some people quite frankly might not be able to hold a group tight enough to notice a difference. The other thought, is that if it did come to an up close situation where you need to "pound rounds", then you are probably close enough that the shift in precision is not going to be noticed. The other elephant in the room is weight. Are you going to be humping it for hours on end, or not. If not, weight savings is a lesser consideration and I would accept small added weight for a barrel type and profile of my choice. For myself in a precision set up in an AR/M4 pattern rifle I prefer a LW SS barrel 14.5" - 18" and 16" would be a good happy medium. If you are wanting longer range, say past 600, the 5.56 will do it, but you should really step up in caliber.
If you are worried about proprietary, or looking for more commonality, interchangeability and availability of parts, then that greatly narrows your list and would move you in the direction of gas impingement in the AR/M4 pattern rifle. While I am not a big fan of a gas piston in an AR/M4 pattern rifle, it is hard to ignore the LWRC / Aimpoint deal. But for a precision rifle, I like the gas piston even less in the AR/M4.
From your list I really do like the Noveske and the SR15, but again the SR15 does have proprietary parts, but are considered to be an extremely rugged and reliable rifle, but they really are different ideas in the purpose of the rifle. If you want a good "battle grade" AR/M4 there are more economical choices that I would opt for while not giving anything up on reliability and durability.