I am a bit lost.
Denatured ethanol is by definition any mixture that is made undrinkable (or nearly so) by addition of some chemicals. Methanol, simplest alcohol is just one of them. Here on can get about 10 different formulations of denatured ethanol (for mostly technical applications) depending on your needs.
Pure methanol burns very cleanly, ethanol is not much worse but propanol tends form soot more easily in my experience. When burning hydrocarbons the longer the carbon chain the more soot they tend to give as a general rule. So longer chain denaturing agents tend to soot more. Glowing soot is usually what gives flame the yellow colour, about the same can be achieved by adding something containing sodium.
I have read that alcohol burns cleanest when it contains a little bit of water but I have never found reliable test data on that, some very good reason for it though, it depends on the temp of the soot particles, the higher the better.
I understand that "meths" usually contains about 10% methanol so the defining ingredient is still ethanol.