Maybe look into adding high pressure air over fire (AOF) on your current rig. When I added it to mine, my refueling went from 7 minutes to 9 minutes and my evaporation climbed by 16%. Check this out: https://mapleresearch.org/wp-content.../combeffic.pdf
What size is you arch? You will notice that the blower size goes by arch width only, not length.
I however have no idea what my pressure nor CFM are. My high pressure blower is over 100 yrs old and is belt driven. It is a paddle blower, meaning it throws the air out (with high pressure) while a squirrel cage blower flings the air (with less pressure). AOF can be done at less cost, many are using bounce house blowers. Likely shorter life blowers, but they give good pressure. When you find the blower in that link, go to Grainger's site and check out the pressure and CFM, then compare it to various bounce house blowers. The pressure is far more important than the CFM, it's the pressure that creates the turbulence in the firebox, burning much more of the wood gasses before they go up the stack.
Dave Klish, I recently ordered a 2x6 wood fired evaporator from A&A Sheet Metal which I will be converting to oil fired
Now have solar, 2x6 finish pan, 5 bank 7x7 filter press, large water jacketed bottler, and tankless water heater.
Recently bought another Gingerich RO, this one was a 125, but a second membrane was added thus is a 250, like I had.
After running a 2x3, a 2x6, 3x8 tapping from 79 taps up to 1320 all woodfired, now I'm going to a 2x6 oil fired and a 200-425 taps.