Maybe they need to introduce the way ammo is in terraria but form it into different kinds of effects. If you use up all the ammo, it will revert back to low power, no special effect energy beams. This opens up a whole new crafting system if they so felt like it, allowing bullets that speed up the farther it goes, ammo that pierces, ammo that bounce, ammo that poisons, burns, confuses, etc.
They are missing out by making weapons themselves that are random and having it depend on suit energy, and STILL be weaker than some melee weapons, despite being a bit harder to find.