I agree with you on this. Reducing the propane in a torch to 10 units is a very drastic change, besides it breaking every mod that requires propane its just unbalanced it seems.
A reduction of 50% would be better, 50 units in a torch seems more balanced for the game in its present state. Still unrealistic but the game needs changes first before such a big reduction.
I'm hoping eventually we can attach the torches to the cylinders like I do IRL. Different size cylinders, the large tanks, the 15lb tanks under grills and the small 1lb camping canisters would be a good addition to the game and by offering varying sizes we can choose which to carry for the job the character is intending to do.