Hi Cheri,
I don't have a lot of practice making a gedcom, but I believe if you were to name the person who will be number 1 in a new gedcom and then create one that divides up those with Portuguese vs. other ancestry, I think you can once again have a nearly 100% Portuguese gedcom.
I do think you might also have to list all descendants of particular oldest ancestors from the non-Portuguese side in order not to miss anyone.
But for me, I don't bother separating them. If I want to know a count, I can use the search with specific criteria. Maybe I can ask for anyone born in Portugal who died in the USA. But this might take some location name revisions on your part. If you don't always name "USA" as part of the location, you can't use that one. You might have to convert all to include USA first.
If I have someone who was born in Pico and want to know how many died in Sacramento, that's easy. And also if I name California it's easy. But if I want all 50 states, I don't use USA on most of my locations. I think the only time I do it is when I don't know exactly where in the USA. I might have their death location as "USA ??." or without the question marks if I'm sure, but still don't know which state.
I have 511 people born on Pico who died in Sacramento, according to my search just now.
Not sure how clearly I've described my idea...
Doug da Rocha Holmes
Sacramento, California
Pico & Terceira Genealogist
916-550-1618