The kenetic beam only really works, when a target facing shields are down. It doesn't bypass shields to do damage. (Would be something if that were the case.) And as for speccing, might as well not bother, as it's essentially a unique weapon, and unless I am mistake, only one can be put on any one ship.
Not to say it's a bad weapon when shields are down. Slices into a hull like a hot knife through butter, and even moreso when the Borg space set tractor beam is also used on the target. Makes ya wana yelp at the devs to reduce the CD on borg tractor, but anywho...
The two piece effect of the set that cutting beam belongs, is not bad too (depending,) though the 3 piece is too short to wonder why it was designed in. Again, anywho...
Best bet, as I've used this weapon on my varous cruisers and the Breen BC cannonship I have going, is to just let the energy weapons tear a good one, and let the cutting beam do it's work. Not much need to respec for it, since when target shields are up, the kenetic beam is a pop gun, and an 'all' kenetic boat would have a hard time against enemies, to say the least.
Yeah its a shame you cant have more than 1 cutting beam. It would enable some really interesting builds considering it doesnt do more damage than a regular beam array anyway and kinetic damage is very weak vs shields. Still, some ship builds would find a full kinetic beam array setup quite useful.
The following are confirmed (by me, in space) to modify the Kinetic Cutting Beam:
Tetryon Glider (2-piece OMEGA set bonus)
Attack Pattern Beta (i.e. the KCB applied the APB debuff to its target)
Directed Energy Modulation
Plasmionic Leech Console
Romulan Embassy Science Consoles (the KCB gets a %chance to leave a plasma DOT-which glows red, not green)[Not sure if multiple consoles give the KCB multiple DOT procs or not]
Global Damage Buffs (AP: Alpha, Go Down Fighting, Tactical Fleet)
Tactical Team (not sure if the skill increase adds DPS to the KCB or not)