The grate looks o.k. The intensity of the burn or the height of the flare can also be controlled with the fuel, and the method of loading the fuel. I only use pellets in my Uuni3 wood fired pizza oven
and they are very expensive, including freight. For my TLUD stove, I use junk wood that I cut with a saw and split with a hatchet. You might try putting a bit of char on top of the pellets. They will slow down the velocity. My TLUD is based on the Anderson Champion, and uses a restriction. The bottom of the pot or fry pan is about 18 cm above the restriction, so the flames just touch the bottom of the pot. Sometimes, if certain very dry wood pyrolyzes too fast, I will add even larger cubes or chunks near the grate. I can always tell when my cooking time is about to end because the flames under the pot will suddenly increase in size. If I still have some cooking to do, then I’ll throw in some cubes or even pieces of charcoal, one at a time to slow things down. When I screen and size my charcoal, sometimes there are pieces of wood that didn’t get converted. I save these for in the stove, and they get a second chance to be quality charcoal.
I might add that I live in the Sub-tropics and pellets are not sold in the stores, so they have to be special ordered. However, there are many invasive species of hardwood that can be cut up into little pieces for fuel.