After 1000 such reviews, It would seem that anyone who is concerned with their rep or badges might lack motivation to continue, stop reviewing and just go back to answering questions. There's nothing wrong with that IMHO, but there may be a flaw in the policy that provides 0 rep for reviewing the close queue and badges that can only be earned once topping out at 1000.
I would work the close queue more regularly if there was at least some incentive for this exceedingly boring, difficult and thankless job.
Idea (that never is going to be implemented ;) )
The review method might be set up smarter. Currently it shows 1 review per item. I believe it would be a bit better for some of the review options if more than 1 topics are lined up below each other and you could mark them all before submitting them.
Where this might be implemented for users with more than a specific reputation and only of the amount of reviews is above a threshold (like 1k+).
Like the other day: Takkat went on a frenzy marking a LOT of topics about "canon" printers against a duplicate. At some point closing them was more a drag than anything else ;)
Oh and if I had my say reviewing would be linked to hats >:-D Here is hoping no meta-SO user sees this