i always thought that +beams or +cannons would be slightly higher then +weapon type (phaser, polaron, etc.) meaning that the generic consoles would get +25 while the specific would get +22
the reasoning being that if you choose to only use beams any cannons u have would suffer or vice versa while taking the weapon specific type would help them both out the same. the only issue i could see being a problem is using more then one of any console but then the trade off would be ay other weapon types they had suffer. (or torps for that matter) etc etc.