As the title suggests, implement mines, manelaying modules, minesweepers, and Micro Momb Launchers into the game.
Mines:
These work like bombs. They sit cloaked on a grid for a length of time, maybe a few days, before despawning. If something passes within 2.5km of it, it decloaks and starts a detonation timer, anywhere from 2-5 seconds, either as a standard value or as a player-set variable, depending on its implementation. When it explodes, it deals a standard bomb’s worth of damage. Maybe it’s omni, or maybe it’s laid in a specific damage type, like bombs. Maybe there could be different sizes, yields, or even neutralizing ones like Void Bombs. Due to abuse around gates, it would likely have the same proximity limits as Mobile Depots, but only restrictions on proximity to gates, stations, customs offices, etc. People can still have their mobile structures, wormholes, and acceleration gates mined. A mine would also be allowed to be placed near another mine.
There are two variables that then need to be considered: whether or not mines damage each other or can be destroyed while cloaked (I think they should be) and whether mines can decloak each other (I think they shouldn’t, but that seems extremely hard to implement). Maybe they are deployed already cloaked, and it takes the activation time before they can be decloaked?
Minelayer:
This module lays a mine. It is loaded with mine ammo and launched like a probe launcher, but it deploys a structure that takes 1 minute to anchor and then cloaks. The anchor time could of course vary.
Minesweeper:
This special ship or module could let a player sweep for mines efficiently. Maybe that means flying really fast with a huge sig radius in order to detonate mines, or maybe it acts like pulses of those mobile observatories, where it can decloak a small proportion of mines (but not ships).
Micro Bomb Launcher:
Cycles like a probe launcher, flies like a bomb, is aimed like an AOE doomsday, and does a whole not a lot of damage. This would be used to destroy large numbers of incoming bombs, fighters, warp disruption probes, missiles, or even small ships, provided you have enough launchers.
Any feedback on these ideas are very much appreciated!