Sauron vs Voldemort

[dehro]

I'm not questioning what a HP wizard "could do"...I'm questioning what they will eventually do, and why.
It seems to me that every time Voldemort is not directly present and actively involved in the battle and magickery, his death eaters show the moral fibre of a broken chamber pot.
at the slightest chance of something bad happening they squabble and run.
Granted, bellatrix and a few other fanatics are exceptions to this rule..but even so...
and I sincerelly think that if the death eaters had a chance of dominating other than by behind the back schemes, they would do so, and in an open confrontation army against army with Sauron, these means don't work.
I am not saying that their magic, when they are put in a corner, won't bring havoc amongst the orcs, but how many, really, can they kill and will they kill before deciding that a solid wall of arrows is working on their nerves? I simply doubt they have the stamina to keep apparating in different places to avoid attacks and the guts to keep fighting against a horde of enemies when they are not directly pushed by Voldy.
when I said previously that Sauron has dedicated henchmen I did so on purpose.. Voldy dominates half of his death eaters through fear, bossing and pain. While this is certainly true also for the goblins and orcs, it must be said that Sauron also has legions of servants who do so of their own free will, and who are really "dedicated" to serving him with their very last breath...
ultimatelly, more than half of the Death Eaters will hide under their bed when things go bad for Voldy. They have done so before, or would all be locked up in azkaban.
as for voldemort's troops other than the death eaters, it seems to me that they are mostly allies and not really motivated by other than maliciousness and a penchant for violence and chaos...and most of them will realize that Sauron has much more to offer in this department than Voldemort ever could.

in other words, how long will it take, once the war is afoot for Voldemort's army to unravel ? how long will he be able to control every single death eater and the strongest allies he has? how many imperio's can he cast in one go?

Sauron has only to say "go" and a very large part of his army will march happily to it's death, because they know that the alternative is much worse... where Voldy has a hard time finding all his death eaters and getting them to do what he wants the way he wants it done... And I'm not going to talk about his allies.

If I understand the "rules" of the game we are talking of one big scrap between 2 armies, right?
if so.. just how many are voldy's allies? He trows them all against the walls of Hogwarts, so there must be room for all of them to fight and walk/fly around.
this gives me the idea that their number is nowere near the tens of thousands bows, spears and clubs Sauron can count on..
(I have a rough figure of 45.000 fighters on the pelennor fields alone, + the army at the black gates of Moria, which was much bigger, presumably around 60,000, but was also stated to be just one of his armies and not the strongest one)

I'm all for magic taking down a couple hunderd foes in one go..but it seems to me that even allowing for a particulary brave, heroic, creative and swift fight from the death eaters (and how many of them have it in them?)...they are heavily outmatched by the "common fighter" alone, even without Sauron pulling out the big guns..