Play editions aren't a bad thing but there's 2 issues with them
1/ they don't sell outside USA
2/ they charge full price
I'm sure point 1 will be addressed if they go this way but point 2 will probably remain. If this is the way it happens I'll be reconsidering going with flagship phones. They've spoilt us with the n4 and 5 prices and it's made flagship phones affordable, personally I don't fancy spending £450 on a phone so would likely opt for something more like they moto g play edition (or the non okay edition for that matter) when it came to changing device next.
It does have advantages though, it will mean Google will be more in control of android updates on more devices and could ride off thee back of other firms marketing. They could also have stock android on lots of non 5 inch devices, I like that the moto g got the treatment, I'd really like to see the Sony xperia z1 compact get it as well. Really one day it would be nice to have the option on a new phone to go stock android or manufacturers, so at first boot you can choose stock or manufacturers version (or even better include something like modacos switch tool).