The difference between energy dampener and mental flailer is that one affects
energy (dampener, the 'disrupt reload time' power) while the other affects
minds (the 'increase reload time' power). So, the Energy Dampener will affect any ship, while the Flailer only affects ships with crews, NOT ships with Master Computers!
I must point out something about the Crystalline Technology trait before you go tinkering with it too much. Besides the 'weak' Shard Cannon you also get Crystalline Armor, which can make a ship or base nearly indestructible in the limited time given for combat. Then there is that pesky Energy Dampener to slow down your ROF. Maybe the reason the Shard Cannon is weak is to give other races a decent chance to survive while pounding on the armor?
Crystalline Tech is a VERY powerful tech for defense.