Well I certainly like the idea of tying Fury of the Unity to deliveance shots rather then culture- It gives at least one subfaction a buff to an underutilized superweapon and makes the bonus more reliably applies- two proverbial birds with one stone.
That said, while stealing income sounds very cool, I worry it will make the deliverance engine's niche(at least for the loyalists) a bit too similar to the Novalith(economic damage first and fomost) only with an eco boost that sort of steps on the toes on embargo.
What about adding secondary effects that either allow the DE to better serve it's existing function or add secondary effects consistant with Advent perks.
Perhaps something like:
Fury of the Unity(requires Deliverance Signal): Increases the projectile speed of Deliverance Engine's shot by 100%. Additionally increases the damage provided by deliverance engine by an additional 15%(up to 40%) and all enemy culture produced at the target planet is reduced by 100%(divided in two as per sins math) for 5 minutes.
[comments: This is the "vanilla" version- it simply focuses on improving what the deliverance engine already does(+dmg & culture) and allows the deliverance engine to better fufill those roles. Cutting enemy culture production in half is worth more then any reasonable static boost to culture produced since culture is defensively worth more per point then it's offensive worth(as we all know 1 culture center can often prevent 2 enemy centers from causing allegiance loss).]
Fury of the Unity(requires Deliverance Signal): Increases the projectile speed of Deliverance Engine's shot by 50%. Additionally your deliverance shots convert unbelievers to the unity's cause: each enemy frigate in the gravity well targeted has a 7.5% chance of being permanently mind-controlled.
[comments: This is probably the most radical option. it also certainly fits well into the Adevtn rebel's penchant for stealing ships. Also it would have two immediate uses: dirstruption by causing part of an unengaged fleet to turn on it's self to waste time, or use in combat to diminish the enemy ranks while bolstering your own.]
Fury of the Unity(requires Deliverance Signal): Increases the projectile speed of Deliverance Engine's shot by 100%. Additionally enemy ships in the targeted gravity well suffer -15% Accuracy and -300% phase jump charge speed.
[comments: With how hard to scratch they already are, adding a defensive boost would certainly be a very large boost to the advent fleet's combat potency. And -300% jump speed ,while not nearly as potent as a phase jump inhibitor(which give -700%), would make the opponent a lot more hesitant to turn tale and flee the buffed gravity well- meaning they are more likely to actually fight, allowing the advent fleet to enjoy its' buff.
Note the Accuracy debuff could just as easily be replaced with an enhanced damage buff as was presented in the first idea, I mostly threw in the accuracy debuff here to display a different mechanic for consideration(nott o mention it was easier to word if both effects are debuffs).]
Fury of the Unity(requires Deliverance Signal): Increases the projectile speed of Deliverance Engine's shot by 100%. Additionally all culture buildings in the gravity well the Deliverance Engine occupies spread culture as though they were also present in the planet targeted by the deliverance shot for 6 minutes.
[comments: Sounds complicated I know, but I rather like it as it would encourage advent loyal players to build deliverance engines at their major culture centers rather then just "Where-ever happens to have spare tactical points and isn't in danger of immediate assault" as is currently the case for ALL superweapons. Not to mention this would create the potential for SCALING culture spread from the Deliverance engine. Have a well that has 4 temples? Shoot an enemy well and produce culture as though you had 4 temples there too for 6 minutes. it also makes massing temples in one location a slightly better proposition as those temples can be made to suddenly be anywhere else with a deliverance shot]
Of course all numbers are meant chiefly as proof of concept rather then as definitive numbers. And there are many many other ways in which deliverance engine could be upgraded tot he same effect-t hose were just the first few to pop into my head.
Heck something with extra Phase-missile-block could also be good- in terms of combat meta-strategy the advent loyals are much more defensive and consequently even more reliant on their shield mitigation then the rebels.
As you may have noticed though, all of my ideas increase the DE's projectile speed. The delievrance engine, due to it's combat boosts has always been the superweapon with the most temperamental timing. unlike the novalith and Kostura where the travel time is mostly just "a warning" before a powerful standalone effect hits a planet, the DE signal needs to be timed to arrive at a battle as the battle begins- a faster travel speed would certainly make the buff more reliable when it's needed most. And frankly IMO a T8 tech combat steroid should be reliable.
anyhow I'm starting to ramble a bit- specific ideas aside, I certainly think there's a ton of potential in changing Fury of the Unity into a Deliverance Engine upgrade.
One last separate point I'd like to make: I'd like to note Fury isn't our only real option to be the advent loyal's "fear me" mechanisms. Alternatively suped up witht he kinks worked out I think both Planet-for-a-Planet And Cowards submissions have the personality and circumstantial activation conditions to fill this role. The message would of course be respectively "be wary of the consequences of taking advent loyal worlds without a definitive fleet/econ advantage" or "Be wary of retreating too often from the advent loyal fleet lest your fleet gradually desserts you".
Despite all my discussion of Revamping Fury of the Unity, these two techs definitely have more built in clought at changing the way opponents have to play against the advent loyals.