Well if all you care about is having lots of big numbers flying across your screen then antiproton is what you want. However if you find that you just don't have enough skill points to properly invest in such a high ranking skill then you won't be gimping yourself by goin with phasers or disrupters.
Plasma isn't all that bad but the problem you run into is that the procs don't stack for more damage. Instead, if a plasma fire proc is active and another one triggers, it just refreshed the duration of the dot. That and at max level the amount of damage the dot does isn't really that much.
That's not to say plasma is bad. Actually no energy type is bad. Its just that the procs of lower tier energy types don't increase with the mk of the weapon so thee numbers may be impressive at commander but at the general/admiral levels those numbers aren't so good comparatively.
I'm assuming since you are making a pure dps build, that you care nothing about ground combat. Get one of the skill planners, don't put any points in ground stuff, and you should have plenty to max out all necessary skills. Take your build to Tribble to test, and see which weapon type you like, at no respec cost to you.