Just an idea that came up from implants, but makes them work more like active modules in an RPG or something like that.
The add-on tree would simply be another tech tree, possibly in the implants tab, or around it somehow. It would add special active abilities to ships of that rank and below, just like implants, but would be active use instead of passive.
They will be used by pressing the five, six, seven, eight, and nine keys.
If an add-on is somehow used before its effect wears off, the effect will not stack.
The other difference is that only one add-on would be available per three ranks, so it works like this:
Where the R13 add-on would only work on ships on tech rank 13 and above, while the rank 1 add-on would work on any ship.
For each rank achievement, there would be one add-on per level in each individual faction, so that if someone levels up one faction, but not others, they are missing out on valuable add-ons. Only one add-on per rank level can be used at a time, just like implants. So you can have the R11 Jericho add-on, but not the Federation R11 add-on, and vice so.
Some suggested add-ons:
R1: Secondary Reactor: “Increases Shield and Energy regeneration by 30% and 25% respectively for 7 seconds. 45s cooldown.”
R4: Exo-Shield: “Creates a small pentagonal barrier shield in the desired direction that persists for 40s. Has 10,000 durability. 40s cooldown.”
R7: Micro-hack: “Shuts down the targeted drone or stationary device instantly. 45s cooldown.”
R10: Secondary Pylons: “Launches a small homing missile at your target that deals damage proportional to your ship size. 20s cooldown.”
R13: Flak Bomb: “Drops a deadly Tungsten-plated bomb where your ship is that detonates after 10 seconds for 10,000 kinetic damage in a 1,200m radius… 60s cooldown.”
R1: Engine Booster: “Boosts your speed by 20% for 10 seconds. 40s cooldown.”
R4: Tactical Regenerator: “Increases maximum hull volume by 12% for 30s. It fills this extra hull space on use. 54s cooldown.”
R7: Phase-Shifter: “Makes you invisible to enemy HUD’s for 5 seconds. 54s cooldown.”
R10: Warp-Shifter: “Creates a small stationary gate 250m in front of your ship that teleports you 2000m forward instantly. Works only twice for you or your team. 60s cooldown.”
R13: Plasma Lance: “Creates a large plasma spear in front of your ship that deals EM damage proportional to your ship speed times 25. Vanishes once you impact. 60s cooldown.”
R1: Multipolarizer: "Increases all hull and shield resistances by 37pts for 6 seconds. 30s cooldown.
R4: Riot-Shield: “Slowly builds a solid shield 250m in front of your ship that absorbs a maximum of 30,000 damage over 30s. Builds up strength at a rate of 3,000pts/s for 10 seconds. 60s cooldown.”
R7: Allegiance: “Removes all harmful effects. 25s cooldown.”
R10: Phantom Drive: “Instantly teleports you to within 1,000m of your target. Leaves you vulnerable for 1 second after jump. 60s cooldown.”
R13: Charge Beam: “Charges up the energy in your capacitor for 2 seconds, then unleashes a 800m long beam of concentrated energy that deals 25,000 Thermal damage over 5 seconds. 70s cooldown.”
And before you go on a rant, realise that these are suggested examples and that numbers can be tweaked.