4 Tachyon lances, 2 ion beams+2 heavy needlers (needler bursts work better for rapidly overloading shields and also for flicking fortress shield on+off), 4 tactical lasers on the forward small mounts, 6 burst lasers for the rear mounts just in case something annoying comes to poke with torpedoes (i could probably swap them out for something else), don't bother with the missile slots. Take the hullmods that make sense (hardened shields, advanced optics, advanced gyros etc.) and fill with max vents and the rest into capacitors.
It's just a boringly OP ship. ludicrous range, perfect hitscan accuracy with its beams that can shred frigate/destroyer shields, bully down cruisers, anything. Fortress shield allows you to either withdraw from combat safely if you've overextended, or trade soft flux for hard flux (basically) during prolonged combat. If you're trading with another capital ship you will always have more flux so all you need to do is trade until the enemy has to start dropping their shields and your tachyon lances and ion beams can disable every single weapon on the enemy ship due to EMP, leaving you free to drop shields for better flux dissapation and more damage dealing.
In the vanilla game the paragon is the only choice for an endgame battleship which is kind of a shame because ballistics are more satisfying to use. Its slow speed isn't a weakness even, it just means that you spend more time slowly crawling forwards before you reach weapons range to wipe out whatever you're fighting.