I've been plotting. Plotting so much I've now come up with a completely different path to the ending of the Rift Runners series, than the one I sold to the publisher.

This happens to me all the time. I think I know what's going to happen  when I start writing and then I start thinking... but what if this.. and what if that...???

Seriously, I don't think I've ever sent in an MS that had much in common with the synopsis I sold my publishers other the names of the main characters, the ending, (which never changes) and the title (which is a never carved in stone). 

And I have to say, except for the main characters, the names are still changing with alarming regularity, too..

Sometimes, you get it right and and sometimes it takes time for a character to find their right name...

Kinda like your kids really...

I have made the naming of characters a ritual. And the wrong name can completely turn a character around.

i wrote a science-fiction novel, and it took 3 years to name one of the secondary characters, but it took me a minute to name the protagonist.
A name should ideally sound unique to the character, as if he/she can't be called anything else.