Dealer's choice of AR15 chambered in 5.56 with a high-candela weapon light, full power MFAL and a 1x red dot/3-5x magnifier is my preferred setup for a general use rifle, to include SHTF. Mine is as follows
- 16in. BCM4 with Mk16 rail and VLTOR IMOD stock
- Surefire M3040DFT Pro, full power PEQ-15, Aimpoint H2/EOTech G33 3x magnifier
- Edgar Sherman Design sling
Not a Gucci setup by any means, but it's the same gun/optic setup I've used over the past decade and I'm confident shooting it both up close and out to the 600-700yd envelope with 55gr. It works during daytime and at night with NODs - checks all the boxes for me. I also will take a bit of reduced output with certain electronics to ensure single-cell usage during times of affected supply chains, where batteries might hard to source; in this vein, I like having any accessories on my gun to be dual-fuel if possible. My preference is onboard storage of CR123s/18350s and a single coin cell battery for my Aimpoint, which gives me anywhere from 5-10 years of constant on from my optic.
Lastly, 2-point adjustable sling is the way to roll as it provides more secure retention and an option for supported shooting for longer shots.