Firstly, you have far too many mods (big ships - at least 7 new destroyers, new race, installations, fighters). Unless you had every modeller in the community making them, you'll never get it done. You're introducing unbalancing technology ('nano-armout', 'beam cannon technology') as an excuse to add infeasible weaponry. presumably because you've not worked out any realistic strategy or story for actually defeating the Shivans.
NTVA is a derivative name. Empirical dictators are cliched, and highly unlikely to arise in a situation where the military forces have been decimated in previous wars (preventing any form of wide-spread security and oppression apparatus).
Despite a plethora of mods, you have no mention of new transports.
It's pretty infeasible to imagine a new race starting a war with the GTwhateverthehell, and then moving to mixed species ships in an alliance within 4 years - just look at the mixed fleets in FS2 after 30 years of alliance. Not to mention which race would join an alliance with 2 species which have went through 4 different froms of government, 2 civil wars and a dictatorship in under 30 years.
Despite this constant war and instability, you have detailed a continuous process of military building which seems to occur entirely independently of the social and economic consequences of war and instability; your best explanation is 'emperors get money from somewhere', which is frankly pathetic.
All of which doesn't matter, because you'll likely never get this finished. A story spanning 50 years, with 14 new GTVA big vessels alone (i.e. ignoring a new race, fighters, bombers, cruisers, transports, sentry guns). Pick a realistic target; something small, but with a well written and tight knit story.
I'm no stranger to futile, stupidly overambitious campaigns - but even I never suggested something on this scale.
