This is borderline a "which is the best ROM" thread and we all know how those turn out. Every ROM I've ever seen claims to be "light and fast" either directly or indirectly..
To the OP.. There are piles and piles of people making ROMs and kernels for this phone. It's one of the most active development communites I've seen in ages. Take advantage of it! No one can pick one for you.. Drop by the development forums, read, read, then read some more.. Pick 5 ROMs that sound up your alley and give them a try.. I'd suggest a ROM a week until you find one you are satisfied with.
Goodluck and enjoy your Nexus!
: Dual boot / Windows 8 & Ubuntu 13.04
i7 2600k @ 4.2GHz / 8GB Mushkin Enhanced Redline @ 1600MHz / GTX 680 Twin Frozr / P8Z68 DELUXE / 2TB/1TB/1TB
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: Nexus 4 / Nexus 10
: Nexus 7 / Nexus S 4G / Galaxy Tab 10.1 / Samsung Epic 4G / Samsung Moment
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