Some ideas for balance and further customization of missiles. I'm just tossing these out here for inspiration.
Improved target leading for AA missiles, perhaps basic velocity based target leading if not already implemented. With flares added and detection on the way, I think it's not unreasonable to make AA missiles a bit more accurate against targets with high tangential velocity.
Guidance and fuse packages reduce maximum length available for warhead and propellant. Currently there's no reason not to use a guidance system.
Fin packages that allow user to customize aero agility vs propellant or warhead capacity, could allow a degree steering (if applicable) even after consuming all propellant. Could also affect max ammo capacity. Can also optionally be used for guided bombs.
Motor packages that allow the user to choose between balanced motor, better thrust vectoring, longer burn time, and better acceleration. Balanced would be the most efficient, whereas others would bias performance in one area for a loss in the other 2 areas. For example, a motor with improved thrust vectoring could be less efficient by using more fuel and/or generating less thrust.
Combined fin / motor package (for simplification), would allow user to adjust agility vs burn time and acceleration
Fin and motor packages would have only moderate changes, such that different missiles would still "feel" different.
The ability to add extra wire length, perhaps at the cost of reducing max available length. This was mentioned by someone else on the FP thread, figured I'd add it here.
Some ideas for balance and further customization of missiles. I'm just tossing these out here for inspiration.
Fin and motor packages would have only moderate changes, such that different missiles would still "feel" different.