Is England now simply “Britain-Lite” and where did the native and immigrant English people go? 

Britain today comprises Scotland, Wales and 7 disparate Regions.
These Regions were arbitrarily carved out of what used to be called "England", by a "British" Government in 1994. In the British devolved government context each Region is now forced to compete, unfairly, with the Scotlish Government and Welsh Assembly for British Government contracts, and in other International/ Domestic bidding contests.

"English" as an ethnic group was permanently removed from the 2012 England and Wales Census form by another "British" Government, so in 2012 English people were purposely 'disappeared' as a unique ethnic group from the Census Statistics. 
Thanks to that "British" Government, native and immigrant ethnic English people officially no longer exist. (Click here for the current meaning of ethnicity ) 

The British Government thereby effectively cleared a path for the re-branding of  England, English history and English cultural heritage as "British" for consumption by future "New British" immigrants.  

England, once a sovereign country with its own native English people might now be best renamed 
BRITAIN-LITE  since "England", "The English" and "Englishness" no longer exist in the "New British" psyche in any form, except domestic and international sport (albeit that people who identify only as "British" or "Irish" are also allowed to compete for England). 

Let me know what you think :   phil@phildrane.com

Cheers, Phil