Never used Motorola Android phone but I'm thinking about buying this one somewhere soon. Does Motorola have a practice of "customizing" stock Android OS? If yes, I guess the only options would be rooting or using some of the Nexus devices, which are honestly too expensive for what they offer. Is it a good phone if all I need is more or less stock KitKat that I can use both for development and as a daily phone.
Nothing on the G is customized the way Samsung does or Motorola in the old day did. Motorola added some useful features but they provide them as Play Store apps. The G is essentially stock Android 4.4.2.
(The comment below referring to voice recognition isn't about the G. It's the X that supports always on hands free voice recognition.)
It uses your address list to figure out if someone is allowed to wake you at night with a phone call: You set a time when you like to sleep, and if someone is 'stared' in your address list, it will ring. Otherwise their call will go to voice mail. There's a handy setting that will allow people who call twice in five minutes to ring you in your sleep.
The changes that Motorola have made are mostly positive (such as the always-on voice recognition and Active Notifications feature). However, it's not hard to remove them.