Moto E3 and Moto C Plus both are of same range. But, Moto C Plus is the one which is overpowering Moto E3 clearly. Let us see how :
VOLTE : C Plus supports VOLTE, which is an essential requirement.
RAM: C Plus has 2 GB RAM which is 100% more than 1 GB RAM of E3. More RAM means more applications can run at same time.
Storage: C Plus has 16GB storage which is 100% more as compared to 8 GB storage of Moto E3. More storage means you can store more media and accommodate all your favorite apps.
Verdict: Clearly, Moto C Plus is a better choice.
No Android Nougat update for Moto E3 power confirms Motorola