The Older Legacy referenced in Ghostly Images art and flavour text (assuming the art and flavour text on this card is consistent) is not Greatest Legacy (notice the difference in their costumes).
That tells me two things. One, Older Legacy is older than Greatest Legacy. Two, the Bunker suit has been in development for a really long time, at least 2 generations earlier than Finest Legacy of our time.
Or, they could simpy be from another timeline.
I'm guessing it's the first Parsons who took up the mantle of "Legacy." It's stated in Finest Legacy's bio that the first Legacy started out in the early 1900s and Finest was born in the '70s. Maybe he'll be in a Pulp Adventure expansion as a promo?
I'm not sure early 1900s is correct. From the online bio: In appreciation for Joseph’s help on that fateful night, Paul Revere crafted a simple but stout silver ring for Joseph, engraved with the phrase, “Furthering your Father’s Legacy.”
Perhaps you're thinking of this: "… in the early 1900s the first member of the family line developed flight"
I don't think I explained my terminology very well. I was referring to the first costumed Parsons that identified as the superhero Legacy, not the first Parsons to develop powers. My apologies!
I understood what you meant. And Arenson might have too if he had read the sentence after the one he quoted. 
I've read a lot of the bios but it seems I missed Legacy. Explains why Joseph named his son Paul and the reason he uses the Lantern as his symbol, knew it had to do with the Revolutionary War, but not exactly how much it meant.
Ohh, a lantern, is that what it's supposed to be? Lol, I'd been wondering for ages, 'cause to me it looked like St. Stephen's Tower but without the clock face, which I knew couldn't've been right because firstly, that'd be weird, and secondly, Legacy (and the game) is America, so why have a London landmark on it, lol.
Yeah it's a weird symbol for someone that doesn't have light-based powers but it works within the character concept once you know the backstory.
Another thing a lot of people have missed in calculating timelines is that comic time is not 1/1 with real time, and characters age much more slowly.
But Paul Parson VIII aged more quickly.
Wait…does that mean there has only been three people with the Legacy title? Or four really old ones? [REDACTED]?
Yes, there have only been 3 that went by the name "Legacy". Our timeline that we have internally is a publication timeline as if Sentinel Comics have been published for the last 80 or so years, not a real-time if-these-characters-were-real-people timeline. Spider-man would be 64 today if comic characters aged properly.
Does that include Pauline?
No. Counting "Young Legacy", there have been four Legacies. Current (America's Finest) Legacy, his daughter (America's Newest), his father (America's Greatest), and his grandfather, who was the first Parsons to take up the Legacy mantle.
Is America's Finest Legacy's grandfather known as America's Oldest Legacy?
I doubt it, because "Oldest" sounds like a retroactive title. He might have called himself "The First" which implies he would train his son to take up the mantle (which the Parsons were probably doing generation to generation anyway), or maybe just Legacy. And if there wasn't a "Greatest Legacy" already I would guess maybe he might have even gone with "The Great Legacy" possibly tying him to the first world war.
Of course that's just one fans guess.
The Legacy to End All Legacies (But Not Really).
Isn't that Iron Legacy? 
Let's see, WWI and Roaring 20s propaganda would suggest Enduring or Triumphant.
Actually 'America's Triumphant Legacy' sounds pretty 20s and enduring sounds really great depression- for the same hero.