I'll start with jet engines, as they are more simple. First, we should be able to change how much fuel they burn, which changes speed and fuel consumption of course, the J15's max being the J50's min, J50's min being J90's low, and so on. This will allow to create more effecient and realistic aircraft. Second, we should be able to change engine shape and size almost as much as the fuselage. However, both forward/backward sides will always be the same size and shape, and the engines' min/max power change depending on the size. Third, for a purchase of 0.99 of whatever currency our devices use, we can have advanced jet engines, which we can change the colour, shape, and size of their flames, give them -2x the minimum and 2x maximum power, depending on their size. They do not replace the normal engines, their flames appear on the building screen as "Trim 3," and they require purchase, unless you're a platinum account (bonus suggestion for getting them for free: log into your SP account and if you have platinum, Advanced Engines are free). Now, time for prop engines. A jammer option for prop engines that is activated by either an activation group or one of the controls. It has a "Power" option that changes how fast it slows the propeller. It is only activated by AGs of course. Another suggestion is an "Interruptor" option for guns, which only makes them able to shoot through propellers at the cost of a slightly lower ROF. The ROF depends on the HP of the prop in its line of fire, with lower HP meaning lower ROF. On the topic of guns, the ability to change their firepower, the one they have now being the highest, as planes get destroyed in an unrealistic 1 hit. I'd like it to be 50 or 100 like it would be in real life. Another suggestion is if they have the highest firepower set, their bullets explode in a small radius when they come in contact with a manmade structure, vehicle, aircraft, or seacraft. This only makes them do slightly more damage to seacraft. I hope these get added in a future update, especially the propeller jammer!