If you want my honest thoughts, I think that the win rewards are completely meaningless. The rewards themselves never justifies the extra time spent in the zone while overleveled. And that's not an 'almost never'... that's a true 'never'. Even acquiring multiple win conditions at once isn't worth it.
I honestly don't care about the military win reward itself. It's just an extra. The real attraction is farming other clans for set+ gear by having them raid my town. This is without a doubt the fastest farming method for scrap items and gear.
I only commented on the diplomatic win reward potentially being lucrative if it could be farmed reasonably fast and the payout is good (to be fair, I've only gotten 1 diplomatic win ever so I don't really remember how good it is). But, in the end, I doubt it matters since you can just get so many more arcane essences and other crafting materials by scrapping the drops of raiding clans.
Though, I must admit that I haven't really raided clans in any recent games due to my recent playstyles (all difficulty mod, non-hc while modding, etc.). So, this might be outdated a bit. But, I doubt it.
In any case, I don't think that the win conditions were ever meant to make you say "WOW I NEED THIS!" They just provide a clear goal and indicator of when a player can consider a zone finished and provide a small extra reward. And, of course, it balances abandoning areas a bit in hardcore by providing a 1 level experience penalty if you don't formally win (even though I think that penalty is negligible).