Yeah, that is some of the worst advice I ever heard. Here's why. It takes 200% power to get 50% more damage. Comparing klink dis 2 to dis 4. It takes 4 energy to get 5 damage out of a dis 2. Double that energy to 8 you get, only 7.5 damage. Whereas dis 4, 10 energy for 10 damage. Same kind of scenario for dis 3, eight to charge, 8 damage. Double power to 16, damage is only 12. Overloading is only for extreme cases with primaries as far as I am concerned and is an in-battle adjustment if you need more hitting power at expense of shields. But I think it is always best to put largest primaries on a ship as you get most bang for buck, especially on a DN. Not to mention that range is better on larger primaries and health and loss of damage over that range.
I think for Neghvar max out on disruptor IV's in forward firing arcs, I dont use polarons, dont like them, hit too infrequently. I use k-torp instead. Max out shields, but maybe not warp core. As a DN, you will be the focus of human attacks, so you will need max shields. And from what I have seen speed doesn't get you much in this game, especially with the slug fest mentality in this game. While it's certainly good to be able to turn at a decent rate, trying to keep up with faster ships is not worth the reduction in fire power. I mean they have to stop turning at some point to fire for accurcary, then their AV will even out and you can get off a good shot. Not to mention that you will be going up against races with larger crunch power than you have as a klink. Q torps and plasma all have higher damage capacity than klink heavies. Hell, a light plasma torp can do 11 damage, while the polaron only does 12. In general neghvar can be pretty agile, so I wouldn't worry too much about manueverability.
As for oveloading shields, this only benefits regen rate. That can be easily defeated by anyone who merely keeps shooting all the time to never allow shields to regen effectively or at all. You need some long periods of time to regain shields for what you put into overcharging.
Those are my recommendations. And if you can fit it, put on rear torps. They can be a nice surprise to someone who likes to get behind you. Hope that helps.