There is NO general best way. What works for YOU is the best way.
I use the names I have and "?" for the names that I do not have.
For those with unknowns I use some extra data:
Mary ? (Wife of John Smith)
? Taylor (Husband of Mary Jones)
I have even at times made entries stating the Mother or Father of such and such.
This will put all of the "Unknown" at the top of the "Index" and I go through the list from time to time and see if there are any "Hints" to the connected person that may give me a clue as to the unknown data. Yes, this makes the Charts and Reports a bit messy but it has helped in getting the unknown data from some readers of these report and charts.