Honor 4C was one of my old phone, and that makes me really reply on this thread!
I remember that this phone never got auto-updates in my region and i had to update manually through OTA. It came with Android 5.0.0, which was very stable. I was excited to update it to Marshmallow but after doing this my battery used to last for less than 50% than in Android 5.0. It was a bit harder to downgrade but i did that successfully. But probably at this time they might have fixed bugs. Internal storage was one of the biggest problem in that phone and it was the reason why i bought another phone.
@Hidden Refuge is also right about so limited storage. Also applications on SD card makes the phone more slower as per my experience. I would suggest you to go for Xiaomi phones, they are good with storage and are good budget phones.