Would it even be in one piece?
Regardless, I'd think that none of the above choices could work (except for merging New Brunswick and Maine together into a New Ireland - the trouble being in a Maine context New Ireland actually referred to a specific place). Either the entire place gets called Sagadahoc (after the failed
Popham Colony) or southern Maine gets called that and northern Maine gets called Madawaska. In that case, Madawaska would probably consist not only of northern Maine but also parts of what IOTL are northern and eastern New Brunswick and adjacent areas of Québec (particularly the Témiscouata RCM).