• A new easily formable fuselage & fuselage wing
• New landing gear with modified properties (similar to simplerocket2, maybe more advanced)
• New designer page for making custom part (custom missile, custom chair, etc.)
• A bit more realistic missile mechanics (proper Fox 1/2/3, still tracking even if the burner is run out, proper countermeasure, etc)
• Advanced weaponry properties (Thrust vectoring missile, IRCCM, gimbal limit, etc.)
• Multiplayer (server and locally)
• more other gamemode (defend the objective, 4v4 dogfight, etc)
• more map with more variety (city map perhaps)
• Simpleship (proper properties / part to make ship)
• More instrument (radar, rwr, fbw mechanics, etc)

perhaps renamed it to simplevehicle (jk, because what can do in here almost limitless while the game name seems limiting to plane)