I don't know if you read the novels, jmampilly
, but if so, you might want to check out A Less Perfect Union
by William Leisner, which is found in Myriad Universes: Infinity's Prism
. The set up is that Earth has remained independent, while the other founding Federation members formed a coalition on their own. It takes place in the TOS era, and IMHO was quite a good story.