An interesting card. It's free to play, and Doomed 1 isn't usually a big deal. No question, it'd be very nice to know the next 5 encounter cards. Other cards that can work with it are Palantir, etc. However, it's only a one-time use when played, and the true cost (as with many 0 cost cards) is, is it worth the deck space?
As much as I love the idea, thematic tie-in, and the great artwork, usually not, as knowing only the next card is often all you need in solo, which can be done repeatedly with ally staples like Henamarth Riversong or Firyal... both of whom can now become heroes thanks to Messenger of the King. Still, I prefer to play two-handed, so they can't completely scry for me.
However, I recently tried a quest, two-handed, where almost 1/3 of the encounter deck had surges, so I thought to combo Far-sighted with the little used Minas Tirith Lampwright... and I'm glad to say it worked well and felt incredibly satisfying, as Far-sighted let me see cards coming in staging, guaranteed Minas Tirith Lampwright to completely cancel cards (at times with their own surge), and I'd either know the upcoming shadow cards, or poised to at least know the encounter cards next round. (If really lucky, they'd include another surge I can cancel.)
Though to make it happen took 6 cards in my deck, which isn't worth it in regular play, but felt good for that scenario. Thankfully, this game doesn't require that I optimize every deck to the max, making Far-sighted a card that can be used for some fun effects, which at times may be more significant than expected, either on its own or when combined with other cards.