Hi JustinM,
Want to hunt predators? Big choice of predators out there to be hunted. To give a better response, just what you aim, pun intended, to hunt will make some adjustments.
I will try to give some useful information.
Little beasts at some distance requires some very good shooting. Yet, many times, is performed from a fixed location. If this is your hunting type, go with a long/er heavy/bull barrel and a bi-pod. Weight is not a concern.
Quick, fast moving beasts that pop up and are gone are another problem to work with. Quicker motion is beneficial. Short/er lighter weight barrels help with this.
Stock types fall into two groups, fixed and collapsible. The fix is normally a little more rigid. Collapsible, more convenient and some/many are sturdy as well.
Chamberings are many. For your stated use, some may not suitable. I would offer that for a first AR, go with a conventional .223/5.56, the Wylde and similar are a good choice. Ammunition is plentiful and cheap(er).
For long/er ranges, look at the 6point8 and 6.5G. This doesn't imply that the .223/5.56 can't do 'it', for it does and in the right hands is excellent.
I currently am working with an AR in 300 AAC Blackout. It provides a greater diameter holes with excellent velocities to 150/175 yards or so. Not ideal for ground hogs at 450 yards. But ideal (my opinion) for wild hogs at the ranges I see them.
Optics? This is directly dependent on what and how far you expect to need/use your AR.
Barrel length adds or reduces velocities, longer for greater, shorter for less. Don't worry, the actual loss or gain per inch is not that great. Long barrels do give a longer sighting radius for iron sights, and this can give better accuracy. Scopes don't care.
No matter what you select, I think that home loads are better than boughten loads. If you don't, think about getting into reloading.
To the weapons.
The top displayed is a 16 inch with collapsible stock.
The lower displayed is a 20 inch with an A2 stock.
I'll carry the 16 incher all day with no complaints. The 20 inch heavy barrel get to be a pain, quick.
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