I would suggest in a future update to make the engines and landing gears resizable and maybe more landing gear (and engine) varieties (adding 4 wheel and six wheel bogeys that can retract into either the wing of fuselage blocks. In addition, resizable piston engines without modding would be a lot easier on people that don't want to add mods.In addition, making the engines resizable (either by giving options for dimensions or just having it autosize to fit the fuselage block it is being attached to) would likely increase the potential for better connections to fuselage blocks as I have noticed with at least one of my planes the engine would wobble sometimes.