Air sealing is the CHEAPEST sort of energy efficiency improvement you'll ever make, and it'll improve both comfort & indoor air quality year round. A 3-5" overblow of cellulose is almost as cheap, but boosts summertime comfort more so than wintertime comfort in a GA climate. Air sealing also protects the structural wood from moisture damage/mold, since exfiltration paths in winter deposit moisture in cold wood, and in summer infiltration paths deposit moisture on the paper facers of the wallboard in air conditioned homes (though it's not nearly as severe for you as it is in south FL or parts of the TX gulf coast.)
Current GA code for new houses has to meet the IRC 2009 air leakage limit of 7 air changes per hour @ 50 Pascal pressure. Your might pass, but I wouldn't count on it. But that spec is dead-easy to meet, even as a retrofit, though most homes in GA built before 2008 see more air leakage than that. But independently of whether that's a government intrusion, it's demonstrably cost-effective in short years, and and going from a >10ACH/50 house to ~3 ACH/50 (a typical result of one pass using blower-door directed air sealing) is a comfort uptick you can FEEL, as is blowing another R10-15 or so of cellulose on top of R19 fiberglass, filling in the voids & compressions.
It took until 2011 for GA to ban active attic ventilation in the building codes, (another intrusion on the free market I s'pose) despite ample evidence going back decades that actively ventilating an attic primarily cools the attic by sucking conditioned air into the attic from the space below through all the leaks in the attic floor, which in turn sucks humid outdoor air into the conditioned space, lowering comfort and increasing energy use. Even without a fan driving it, the stack effect does some of the same, though it's an order of magnitude or so lower. But the comparative infra-red radiation opacity of cellulose to low-density fiberglass has as much to do with summertime comfort and cooling load reduction as the additional R value.
So, you can either sacrifice comfort & cooling/heating expenses on the altar of free market principles, or judiciously apply building science & financial investment principles to make it a more comfortable home, it's completely up to you. But I doubt there's any legal or safe investment available to you with better after-tax returns than the modest improvements suggested.
This isn't much different than pointing out to somebody that their left-rear tire looks a bit low- drive on it the way it is if you like, but it'll handle better and last longer if you take the time to give it some air. If you plan on living in the house one more year a decent DIY round of air sealing will more than pay for itself. A DIY cellulose overblow to restore the performance of the fiberglass and maybe a bit more could take 5 years to pay off or it might take 3- hard to tell without a more detailed inspection. If you let the pros do it the financial payback will take longer, but they might do more, and fix & find the less-obvious leaks, improving comfort & efficiency more (or not- depends on the pro.) With the drive for new nukes going on in GA I don't expect electricity to do anything but rise over the next decade, given the huge capitalization costs of the project, so payoff can be quicker than how it first pencils out.