Okay, I'll try to whittle this down as much as possible.
You say power and fear keep everyone in line, but power and fear alone aren't what maintains allegiances and keeps a galaxy-wide organization cohesive and running smoothly. You say his underlings assume the bulk of this work. But who appoints everybody? Issues orders? Formulates plans? Dispatches soldiers? Fires and hires and promotes? Makes any sort of decision? Freeza! (In fact, Sorbet is shown in the first chapter of the manga adaptation to be dealing with - rather poorly - with precisely these sorts of things in Freeza's stead.) And you say it would be outright out of character for Freeza to take on such tasks? I'm sorry, I don't follow.
I think one possible point of interest from the manga chapter is when, as Sorbet and Tagoma are heading back to HQ after Earth, the latter issues a caveat to the whole Freeza resurrection plan - "But wasn't he a dictator?" - and wonders whether he really has the "ability" to bring everything back under tight rein. Why is it that he doubts whether bringing Freeza back was such a good idea on account of the tyrannical character of his rule, if such is exactly what makes him a valuable leader and is the sole reason why they needed him back in first place? Why does Tagoma, on top of this, refer to "ability", and not to strength?
In view of this, there's plenty good reason to think, instead, that Freeza would be able restore at least some semblance of order simply because, in addition to his power, he's the competent former ruler of the empire (which it is, for all intents and purposes), who has decades of experience leading so large a mass across so wide a space and will no doubt prove capable of re-instituting the requisite rigor and discipline in its ranks using the power at his disposal. Someone with power alone isn't necessarily able to do these things with any success. Power by its lonesome is all fine and dandy, but it has to be used well if there's to be any form of lasting stability: Quelling an insurrection here, an insurrection there ain't gonna cut it in the long run if this power isn't consolidated around a centralized authority figure, like Freeza, who knows how to use his power in effective ways as to, as you say, "inspire fear" and keep the whole structure stable and running in the long term.
Again, had Sorbet or Tagoma or anyone in any way suggested that Freeza's power was the one and only thing that mattered I'd be glad to concede the point - anything, even a throwaway line like, "Is Freeza really that strong?", from Tagoma to Sorbet in their little exchange or really anything to this effect which likewise indicated that strength is what they're really in desperate need of. Also, you seem to be assuming - rather unfairly, might I add - that I'm somehow having to bend myself over backwards to excuse a plot hole that's evidently right there for all to plainly see. But yours was not my first reading, nor, I suspect, was it for many others.
All I see is Sorbet being incompetent and simply needing to bring back his far more able former boss with the "ability" to bring things back to form - nothing more, nothing else. Nowhere, as you would have it, is power made out to be the central issue here. Nowhere does Sorbet say "Gah, we're so weak... But if only Freeza-sama were here!" or even remotely suggest it (in fact, Sorbet vaunts the strength of his soldiers, comparing Tagoma to Zarbon). Believe me when I tell you that I'm not one to try and give clear inconsistencies a pass by means of over-extravagant rationalizations, nor do I have any qualms at all about calling what I think to be a plot hole out for what it is. Cell's nucleus? Plot hole. Everyone remembering Boo in the JSAT special? Plot hole. The number of wishes in Battle of Gods? Plot hole. Bulma's age in the same film? Plot hole. I just don't see it here, taking the information purely at face-value.
EDIT: Also, yes - this is me trying to "whittle things down". Hem. Apologies.
on a sidenote still hyped about this movie coming out! gonna watch it in 4Dx3D!!!!
