
The correct point of comparison comparison for this card is Scavenging (2). It's a card that saves you multiple play actions. Although it doesn't recur from your discard, you're a seeker — you too can do "recursion" it the au naturale way, by simply cycling through your entire deck.
The point of the upgrade isn't to play 2 assets although it's a nice option to have if you have two cheap assets, or you're an Amanda with RGM out. Unlike the 0xp version, this one saves an action because it's also an investigate action, one which you can also manipulate the DC of (Ancient Stone anyone?).
Seekers have no shortage of assets they want to play over and over again. Ancient Stone, The Necronomicon, Mr. "Rook", or the new Eon Chart...some of those are even Relic traited, further increasing efficiency. You can use a charge from your Eon Chart to investigate to play a new Eon Chart as a fast investigate!
Unearth the Ancients is not a simple economy card. You can't expect to throw this into a deck like a Crack the Case or Cryptic Research and have it work — it's acceleration for already powerful decks where you'd play it multiple times over the course of the game. Some of the power Seekers have lost to Taboos, they've regained with Unearth the Ancients, though arguably in a much fairer manner as Unearth the Ancients is susceptible to the dreaded .