I like my AR's and haven't had any issues with them. I've been thinking about adding an LR-308 to my collection so that I'd have a bit more grunt if I need it.
Ruger Mini-14 is a good alternative. If you like the AK platform, you could just stick with that.
For home defense, stick with either a handgun or consider a shotgun. Rifles are noted for over penetrating. You don't want to shoot through the bad guy standing there in your bedroom doorway at zero-dark:30 and end up plugging your neighbor as well.
“Depends on how much you like the AK. It also depends on what you plan on doing with it. Plinking? 3-gun? Long range? 50-200 yrds only? What price range are you thinking? What part of the US will you be living in? What is your ammo budget like?”
A lot of questions. My price range is up to 2,000. I live in California unfortunately for the 2nd amendment. I am not quite sure how to kanban ammo yet.