If you're going to run that many beam weapons then an EPS flow regulator is an absolute must. You'll need it to keep all those beams powered up or they won't be firing at full power. I have this same setup on an assault cruiser that works well.
You donít really need EPS for firing the weapons just changing power settings in mid fight or dropping from max impulse. I run 6 Beam Arrays on my broadside Cruiser with 3 x +6 Weapon Power consoles and 1 EPS. For running lots of weapons its best to go 125 weapon power and have multiple copies of EP:W. The EP:W wont help with the max weapon power since your already at 125, it really helps as a buffer for weapon power drain. Instead of your power dropping to 65 from 125 when you fire all 6 weapons it now only drops to 85 so you do much more DPS in the long run.