Doing a little more research and more measuring, this is the best cooling I can get for this system. Unfortunately, Gigabyte has some housing right where a bigger fan would need to go, so the bigger fans/pipes/fins probably would not fit on this motherboard. I don't think it's a deal breaker, though. I added a second fan to the fins, and the temperatures dropped another 5 C during normal use. They still get to 70 C under 100% load, but that's not that high for this CPU. Other reviews I've read have said that the lids used on these CPUs are connected to the case in a manner that limits thermal dissipation, so without delidding the chip, I probably won't see much better temperatures.
I'll just have to bear the noise from the fans from time to time or make sure music/tv/movies/etc. are on in the background.
