No power bank will be too much for your Moto E, all power banks are okay to use on any phone, they can't overload them. you say you are looking at a 5600m or 10400m, well go for the 10400m because it will store more power and keep your phone charged longer. I personally use a TeckNet PowerZen G2 9600mAh.
I have a Motorola Moto E 1st generation. I have been browsing for power banks for it today. They come in various powers, and I was wondering how much power might be too much? I have my eye on a 5600m bank and also a 10400m. I need to know if these would bee too much for my phone. I appreciate any input.