The problem I have with the ability is that essentially only exists to compensate for weaknesses inherent with cruisers and beam weapons.
In any case, my intention was to merge EPS and Nadion, not Nadion and DEM. Nadion would be somewhat more useful if it was not only merged with EPS to provide power boost+resistance, but was also transferable. As for DEM, making it an Engineer Captain skill would give them something of a direct damage skill and by extension, would help out cruiser captains by giving them an offensive skill without having to give up the highly useful Lt Cmdr and Cmdr Engineering for it.
DEM is rather weak and hardly worth it by comparison to NI. Also you do realize that NI actually does more than just keep your weapons power maxed right? It stops enemies from draining your power and even lessons the effect of things like Tachyon beam on your shields. (I know it does not matter when players use their super nerfed Tickle Beam version but the Borg version still works.)