I would like to put this to the community at large as a good solution for border and other protection uses.
I have read complaints about border protection and how the ships just roam freely into and out of each others space.
I agree that a solution is needed and here it may lie. There should be more risk in entering anothers territory.
The use of mine-layers and mine-sweepers in the form a special ship or just a module - either way
the mine layer and sweeper modules could be laid by a specialized ship or just an add-on. The removal of said mines could take a certain number of turns to remove with a ship so equipped. The mines would explode based on proximity of course. They could even have some variety of effects, some damage of course, some dispersion, maybe even a black hole mine that could suck ships into it. All being said, the question of border fortification would be solved. Of course the tech tree would have to be modded.
Thanks For your constructive comments - perhaps if we kick this around together we can come up with a great spacemine-based solution.