Hey all. I've been playing KSP for a while and downloaded a few part plug ins like B9 Aerospace Pack Nova Punch RLA Electric Engines ... I needed them mainly because I wanted a bigger/smaller type of some part. While this solution works well enough, it has some downsides: There are simply too many parts. Finding the right means navigating thru many pages. Many parts are similar in their function with only a few differences (based mainly on size). Capacity for tanks and thrust for engines for example. This makes a lot of the parts redundant. Implementing a new size means adding a lot of parts which are basicaly already there, just not in the right configuration. My suggestion is to have configurable parts. This means that, for example, you can choose a "RT-10 Solid Fuel Booster" and configure it to your needs setting some parameters like: Diameter, where you can choose from the available sizes Length, where you again can choose from the available sizes and which increases the fuel capacity and length of the tank of course Lifting capability, where you can choose between "Heavy Lifter" which has a high thrust and short burning time, "Standard" and "Endurance" with lower thrust but longer burning time. (maybe more than 3 steps, or even as a slider) Other parts can have other configurable properties. Here are some properties which come to my mind: FuelType, or empty (for tanks) Light Weight ... Heavy Duty. Increases\decreases weight, impact tollerance, shear force. (for structural, wheels, landing strut/gear) Re-entry Capability. Adds some wight (and maybe a nice texture) and makes the part survive a re-entry. Semi-DeployedDrag, Fully-Deployed Drag, Diploy Altitude (for parachutes) Optimal Speed, Maximum Speed, Optimal Height (for Jet Engines) You get the idea. Configurable parts would greatly reduce the parts in the part browser, make it easy to implement new sizes and give the user more control in their design. I'm aware that this is similar to: http://forum.kerbalspaceprogram.com/threads/59401-Tweakables-contextual-parts-and-fuel-selection but think this is a different approach, because it's focused on configurations rather then centext.