If I recall from reading the faq about the update, it says there's no going backwards. I don't know for sure though. Maybe you can follow the directions on Motorola's website and flash the older firmware.

 

Generally speaking, it requires being rooted to flash an older firmware.
What are the changes you don't like? Sometimes there are apps or themes that can alleviate those issues.

 

Or you could wait for a custom rom and flash it.

 

The color change is refreshing for me since I've been living with it like that for a few years.
You can try a third party dialer app from the Play Store.
Since I don't use my Moto G as a phone, I can't say for sure, but with KK on G2, in the dialer you can hit settings and clear the call history.

 

Took me forever to get used to this white and gray but I did, like the guys here said there is a few ways I for one recommend unlocking your bootloader flashing a recovery and going probam then installing a theme don't like white but love green go for it..

 

I believe CM11 has the blue icons, you could flash it an check. Once rooted you should be able to customize the status bar

https://play.google.com/store/apps/details?id=com.jy.iconchanger.ad&hl=en

Use whatever settings icon you want!

Get a new dialer, I think the KK dialer sucks but there are plenty of dialer replacements in the app store. I used exDialer myself. And I change the icon using that icon changer so my home screen looks the same.

You could do that but before you do I would try rooting and flashing a custom ROM. You should be able to get it looking just how you like.

 

Yes I remember reading that you can't go back. Honesty I haven't noticed many changes. Still use it the same tho. I did the upgrade while not connected to my charger and it consumed 40% of my battery.