To root an Android device we need exploits, but when we already have a method to root(Unlocking BL), no one is looking for them. So hopes of rooting without unlocking Bootloader are slim. I too am waiting for Motorola to stop providing updates to our Moto E, then only I'll unlock Bootloader and root and install CM, Slim, etc... Hope that helps!
A happy user of a Moto E (XT1022).
Press Thanks if I helped.
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