By just removing the bottom of the 3 springs you now have the equal of the stock trailer with the 8" wheels. Take out the other spring so that there is just one on each side.
I looked at flipping the axle to the top of the spring to lower the trailer, but this would have required making new fender mounts to keep the tires from rubbing on the fenders when loaded or hitting a bump in the road. With the 12" tires it might be worth it to get the trailer more level.
In my 8" tire I have found 20 PSI to be the best. Fully loaded and at the end of a tank of gas at interstate speeds the tires and bearings were still cool to the touch. I could probably go a little lower yet on air pressure. Mine bounced like crazy with 2 leafs, the single leaf and lower tire pressure got rid of the bounce even when empty.
I am still looking at adding the 7" electric brakes from R&P Carriage, and of course, more lights.
But then, now I might have a line on a Bunkhouse in which case I will be selling this trailer.