Dino: I'm impressed with your shafts. Most folks don't take it that far. You'll end up with 630-650 grain cedars depending on the heads you use, which is pretty potent medicine, and in cedar to boot.
I've been shooting cedar for about 40 years and have always been looking for ways to make it heavier. In addition to footing, soaking the shafts in watco oil and compressing them are two ways to get heavier shafts in a smaller diameter.
To start, I always look for the physically heaviest 11/32 shafts I can find in my spine range. Soaking them them in watco or a similar oil adds about 50 grains. 23/64 shafts would no doubt gain a little more.
Soaking doesn't work very well with shafts that were compressed by running them through a die, however. But compressing can also give me a heavier shaft. No, compressing doesn't make the shafts heavier, but it takes a heavier 23/64 shaft and compresses it to the 11/32 diameter I use.
One of my shooting partners and I are working on another way to increase weight and FOC on cedars -- an internal steel footing. We drill a 3/16 hole about three inches into the point end of the shaft and then epoxy in a steel rod (about 100 grains). Made a few with a power hand drill, but really need a drill press to do it right. Haven't been able to test outside yet, or do any kind of testing for durability. But since the steel rod extends for two inches behind the head, it should strengthen the front of the arrow considerably. Will be interesting to see if these things work. If they do, should be able to get up to the 700 grain range and a high FOC, guessing in the 18% range.
It's been a long winter here. Obviously left me with a little time to tinker.