I understand that this is considered to be on the "do not post" list, but this is not simply "change the order so that part X is before part Y and Z" 1. Currently fuel tanks and engines are grouped into one tab, propulsion. Also, the Jet fuselage and structural piece are in separate tab, which can become slightly confusing. I would recommend splitting up the engines and fuel tanks into two different tabs (something like propulsion and tanks, engines and containers, etc.) 2. In addition to this, you could right-click and select if you wanted the part to be a structural piece, LFO, etc. (much like the b9 mod does things)(http://forum.kerbalspaceprogram.com/threads/92630-0-24-2-B9-Aerospace-Release-5-2-1-(updated-07-09-14)) 3. Lastly, if you devs don't like the ideas mentioned above with right clicking to change the part, it you could have it so that when the "tweakable fuel sliders" are set to 0, the part turns into a structural piece that would be lighter then an empty fuel tank (but cant change fuel) Thanks your consideration, and good luck further developing the game!