I've thought about this and can't for the life of me figure out what the advantages are over using a "gate monitor" type of ship (as Steve uses in a few of his fictions). The space station idea seems like it would be something you could just place and forget, say with 10 years of intended deployment, but honestly you'd just end up seeing the weapons go obsolete and wonder why you spent so many build points on something big and immobile that can't be used for alternate purposes (and that the enemy will not be surprised by twice). Instead just design a ship with 2+ years of deployment time that has lots of short-range energy weapons, with maybe only one engine and a little fuel storage. That'll allow you to move it to a jump point, ambush anybody that comes through, and move under its own power if needed elsewhere or if it's time for maintenance/refit. Or, just make it a regular thing that when new energy ships enter your fleet, the second-newest models get rotated to jump point duty, and the third-newest get scrapped or recycled.