Watch the entire thing; a very reasonable presentation
Key points:
- DI better than piston due to weight (I could debate his reliability claim based on lube availability)
- iron sights or optic with no batteries
- light should be dual purpose (removable)
- is 5.56 "really" better than 308 if you could only have ONE rifle (I could debate the ammo weight)
His recommendations:
- SCAR 17
- or basic milspec 5.56 carbine with no extras on it
- both with ACOG or iron sights