Nice work Pan,
Welding is kinda like smoking, once you try it, its like the flu. A bad bug that wont go away. It makes you look for stuff to weld up.
If you only burned thru a few times you are doing great man. And especially since you are using flux core wire. A few things to think about are maybe try using some cheep cooking spray as a anti splatter spray. It helps greatly for the clean up. If you have trouble burning thru try using a piece of flat copper as a heat sink on the back side. Alot of times just a scrap piece of 1/2 or 3/4 inch tubing will work after you smash it flat.
Hey, look at it this way. Its a drum, no structural parts involved so play with it. Turn it up turn it down run fast run slow and so on. BUT pay attention to gun angle, and how much stick out you have between the tip and the part. This is where most trouble starts.
I have never ran any real thin material with my stick welder, just 1/16" stainless. Maybe I could go thinner on stainless but I bet not on mild steel. This is only my opinion of course.
Pan from experience I can say usually the pics will turn out better in natural light vs flash. The weld tends to reflect the light very bad making a really shinny picture.
Nice Work and good luck with your welding future.