feels like u are misguided, you are comparing a just launched Moto g, with a one and a half year old 820 and more than year old 720, and then u are complaining about the ram screen and battery life.
And if u are comparing it with upcoming lumia 630, may i just remind u a lumia 520 (512 mb ram) with 8.1 broke a record set by galaxy s4(2gb quad core bla bla..), for its all new keyboard u wont get on Moto g, plus nokia clearback tech, gorilla glass 3, all new sensorcore tech, and the fluidity of a windows phone 8 os, which just got way better with all those enhancements done in wp 8.1, check task manager of your Moto g, u will not get more than 500mb ram free with no app running, while wp still has 350+mb ram free for apps.
And i bet u keep a 630, and a Moto g side by side, u will only get disappointed by the later, for its sluggishness.
Also u can hook up 128gb memcard, u wont find a place to insert it into your Moto g, limited with 16gigs(maybe around 10gig actual)
I agree wp is a step backward with its app and games, then again run asphalt 8 on your Moto, and compare with a 520.
Now u may get the fuller picture...