Weapons were the most difficult thing for me to settle on. In the end I compromised by going for full-weight beams. I wanted a more exotic solution in the center hardpoint, and tried the frags, which was a mistake. The lightweight corrosive multicannon helps keep mass down, is low draw, and the corrosive bonus plays well with the beams. I can stay and fight for a long time since I just fire the odd burst with the MC to keep the bonus ticking and ammo lasts a long time. The beams on their own don't drain the capacitor. If I fire all three it would eventually. So the DPS is 'true' because it can be continuously fired for a long time. Damage per minute or something would be more useful than DPS with Elite weapons when evaluating a build I think.
If I could add corrosive to a cannon I would have tried that too. That range is really nice, with no falloff.
When you're ready to fight with it let me know. We'll do some bounty hunting.