A fun and relatively simple side quest (appropriate to a starter desk), although 5 actions is a lot. Few Seekers are going to want to a third of 5 turns doing Draw actions to get a shot at an upgrade that will be useful only to Big Hand decks. Eldritch Sophist will helps you pull secrets off it, but that's a pretty thin combo.
More urgently, what happens if you do your last draw, have no secrets left, but don't have 10 cards in hand? Do you hang onto the tome until you hit 5 cards in hand? Have you missed your chance to translate it?