To your point, its not for open cooking, but for pot cooking (i.e. boiling water). For open cooking, I like the firehole method - dig 2 narrow holes parallel to each other straight down. Then at the bottom, dig a tunnel between them. Use the dirt to build a berm around them. Build a fire at the bottom of one, places some stones around the mouth, and then place a grate on the stones for your grill. When you're done, put the fire out, then use the dirt to fill it all back in. Very very low signature, very low foot print, great heat output. You can also use a skewer to cook over it if you don't have a grate.
I've tried numerous DIY stove variations, for a woodgas burner, the J. Falk stove has been the champ. And after trying several DIY alcohol burners, I bought a Trangea. Bombproof, and you can seal 3oz of fuel in the stove itself, comes with a cover that regulates the flow. A full stove will last for hours if you need to keep something hot. I use denatured, and heet, but it'll take anything alcohol. Just the less alcohol, the more soot it puts off.