I've rooted my nexus 4 and used at least 5 different ROMs over the past few months. Only to realize that they are not that much different from the stock ROM. You do get a few more options in settings that allow for more customizing. But honestly its not that much more. Some can be done without a custom ROM thru apps from the play store. If you have a Note 2 HTC one S4 etc...then you see a huge difference when using a custom ROM. It gets rid of your ui and gives you stock Android. But on a Nexus devise you already have it. I can see the benefits of rooting in order to use certain apps that otherwise you couldn't but you can root without using a custom ROM. The stock ROM to me works just fine on a Nexus. Does anyone else agree with this and if not why not?
From my Nexus 4 via Android Central App
On of the main goals of ROMs on non-Nexus devices is usually to give users a stock experience. So yes, we already have that with Nexus devices and yes generally speaking the stock experience is damn good, making the "need" to use a custom ROM less on Nexus devices. But that doesn't mean people don't just want to.
These devices are purpose built to be easy to tinker with and that's what many of us like to do. If you look at things like AOKP and CM, they tend to "look" stock but really the code base is vastly different and has been built up and changed over the years. They have some very specific and unique features that aren't in stock and that's great. It's good for Android as a whole and it's good for users who want something that isn't exactly stock.
Even the more stocky ROMs that are closer to AOSP than ROMs like CM and AKOP still bring things to the table. If you can find one that has all of what you like in the stock ROM and none of what you don't (ahhh, I miss you Bugless Beast!) and you get behind that dev then you have the best of both worlds.
So I don't really agree, Android's always been about choice. Out of the box, Nexus devices offer a great experience and users don't (and shouldn't) have to care about any of this. But Android from the word go has also been about the hacker tinker community and I think that should and will always be part of the Nexus experience.
But I see you're point, why do people spend time making (and installing) ROMs that are really not that far off of the stock experience? Because they can and that's awesome.