Yeah, the cheap ammo "honeymoon" is over for AK owners. We only have one 7.62x39 rifle and it is a bolt gun. Originally I was going to rechamber it in 6.5 Grendel, but the thrill of shooting at (then) 7¢/rd instead of (then) $1/rd killed that Grendel bolt gun project. Now you can get a variety of off-the-shelf Grendel bolt guns, e.g., CZ527 variants and the Howa Micro-Mausers.
Years ago I thinned our collection based on "mission suitability." I sold off some German, Austrian, and Swiss rifles (and now regret it because they have skyrocketed in value). I sold off my AUGs incl. a selective fire version. I decided that the inability to shoot "weak side" made it less useful for the mission (family defense). They were great for competition, but because AUGs were ruling the top spots, match directors eventually started designing stages that forced "weak side." The AUgs became even a competition disadvantage.