I agree you're making this harder than it really is, or you're trying to justify the expense. The AR10 platform is decent, but expensive. Far cheaper to get a dedicated hunting gun, and an ar15 platform. 7.62/308 is not an ideal round for home defense, period. Rural defense its ok, it has a longer intended range. For it, 20" would be the minimum. Better off buying a lever gun, as it can serve both purposes as well. It is politically less volatile, lower key, compact and can be powerful or mundane. When AR stuff became unobtanium after last December, I picked up an extra lever gun to fill the need.