Daisy Walker - Working with what I have

As far as EXP upgrades, things to consider:

--Encyclopedia (2) is a powerful general-purpose Tome. (Be careful to note, though, that Daisy's bonus action will still provoke attacks of opportunity, so it's hard to use it to evade, and you can only use the bonus action during your turn.)

--Abigail Foreman (4) lets you turbo-Daisy (although she doesn't work with Dream Diary, unfortunately, except for saving the handslot). Also feel free to spend 3exp and write "Charisma (3)" on a slip of paper or your campaign log. There's no reason not to have that option available to yourself, since it's such a trivial proxy.

--Segment of Onyx (1) (your cardpool is too small to worry about most taboos) is very powerful and quite findable with repeated Old Book of Lore activations (also remember that it's Myriad and so is cheaper exp-wise).

--I can confirm that The Eye of Truth (5) feels awesome, but it's also very expensive exp-wise and doesn't particularly synergize with the rest of the deck at present.

--Disc of Itzamna (2) is good for enemy-management in fighter-less parties, but is also pretty expensive resource-wise and competes with St/ Hubert's Key (although like Charisma, it's perfectly acceptable to just spend 3 exp and write "Relic Hunter (3)" on a scrap of paper/in the campaign log, should you consider that worth it.)

--You have access to Ward of Protection (2) which is very good, although I saw your reddit post stating that she's paired with Wendy (who's very resilient to treacheries), so it may be more of a luxury.

--Cryptic Research (4)/No Stone Unturned (5) are perfectly fine experience-dumps, should you find yourself with a glut of exp (minor mechanical campaign SPOILERS for Dream-Eaters: the A side (Dream-Quest) has a LOT of potential exp in it -- theoretically as much as 31 exp by the end of scenario 2, although getting all of that is difficult or may even be inadvisable...).

--Magnifying Glass (1)/Magnifying Glass is also never a bad card for Seekers, although you have a bunch of ways to replicate the effect (and hand slots are more valuable than usual).

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Also, remember that Scroll of Prophecies uses secrets, so you can recharge it with Astounding Revelation if you don't need the resources - however, resources are probably more valuable than cards in this deck. You may even find yourself missing the Emergency Caches as a way to supplement Astounding Revelation, fair warning. (This is one reason why I don't like cards like Arcane Studies, unless you are absolutely rolling in resources (and even then they eat an action to play).)

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From the packs you're missing:

Point of No Return has the Dream Diary upgrades. Any of them are good, though Dreams of a Madman (3) is probably the best for Daisy-with-Wendy, as an evasion tool (or Shrivelling-boost). Upgrading just one Dream Diary and keeping the other un-upgraded to use with Daisy's ability is also a solid idea, as it potentially enables multiple Essence of the Dream uses per turn. Empower Self (Acuity) (2) is also from this pack, which could be good if you want to lean more into -using cards.

A Thousand Shapes of Horror has the interesting Otherworld Codex (2). How good it is depends on campaign/scenario, but as a 1-of in Daisy it could be neat.

If you get A Phantom of Truth, be aware the Archaic Glyphs upgrades aren't Tomes for whatever reason (they're just Spells), unlike the base version you technically have access to at the moment. I don't know why the designers made this decision, but it seems like a specifically feel-bad trap for Daisy players at the time (there's no reason they couldn't have been both Tomes AND Spells, to be used by both Daisy and Akachi).

Dark Side of the Moon has Practice Makes Perfect which can trigger Astounding Revelation and find Deduction, but you'd really want Perception and/or The Eye of Truth (5) as additional targets.

Where the Gods Dwell has Old Book of Lore (3), a great upgrade, and Summoned Hound (1) which could be good for enemy management as long as you have a plan for the Bad Dog.

Great advice, thank you! Good point about resources, I think I will end up wasting 2x cards keeping the arcane studies in there and not having the extra emergency caches. I'm considering just removing the arcane studies cards (Mind Over Matter can probably suit in a pinch)

@mdespaultTo note, Mind over Matter does not apply to things, like you seem to be implying. It only affects and things (and only during your turn). Mostly useful for removing a Locked Door (though Wendy is probably pretty good at that), evading an enemy (maybe two), or punching a 1-health enemy (or maybe two).

@anaphysikMy thinking with mind over matter (and another reason why I think Arcane Studies ends up being a waste for my deck) is to be very situational for emergencies where I need Daisy to attack. Using her 5 paired with the +1 from St. Hubert's Key and +1 from Dr. Milan Christopher would give me a skill of 7. The downside, besides being situational, would be a single damage point (maybe it would be better to flee). The more I'm learning about all these other cards and synergies though, I wonder if there are better cards to achieve a similar purpose

Well, some enemies are specifically-designed to punish simply evading them. (I'm assuming you're familiar with the Core scenario cards (but not the other campaigns' ones); if somehow not, then obviously just play and discover. Even with familiarity, just playing through The Gathering/Midnight Masks with an iteration of the decks will tell you a lot about how well they work). I don't think I've ever actually used Mind over Matter in Night of the Zealot except during my very first playthrough when poor Roland was stuck with it in his deck for a scenario, but I'm guessing would be very useful for Daisy+Wendy, as an answer to Cultists and potentially even the lowly Rats (although 2 is a lot better than 1 against Rats). I suggested Lantern for the Wendy deck over Flashlight for the same reason. Mind over Matter is also probably very useful in The Devourer Below due to the annoying clue mechanics there.