Thanks all - appreciate the input.
This was where I was when I came to post the original question:
I was importing my gedcom in and came across this family already in WikiTree. So was thinking of connecting in. Because it was a pre 1700 profile an auto generated message popped up that lead me here.
So from my standpoint at that moment in time I can see how the existence of these people is plausible due to a series of sourced interconnected relationships that lead back to myself, as I am looking at my tree at the same time as WikiTree.
My thinking was to put up a sourced link to a person on family search in the hope that others would also recognise another series of interconnected relationships as otherwise they are only working with the interconnected relationships on WikiTree.
So was hoping this would provide a bit of a family context to someone who knows the family to try and work at getting the person in in the best way possible.
I have a few more post 1700 relationships that I can add in which might (well definitely) have been a better thing to do before approaching it in this way so in the meantime will work on them!
In terms of 'a' source for this relationship I was thinking:
"England Births and Christenings, 1538-1975", database, FamilySearch (https://familysearch.org/ark:/61903/1:1:JQ8W-7XD : 21 July 2021), John Cumberland in entry for Thomas Cumberland, 1679.
Thanks again in advance for any further input!