It's Fine - Going Solo with Jacq.

Clues gathering:
Clairvoyance is an obvious choice for this deck. This is solid card for Jacqueline, who can easily mitagate it's donwnside with her ability. While building this deck I tested other options for boosting Intellect\lowering shroud (like Flashlight or Perception) not to rely solely on one asset, but I realised, 3 Intellect is most of the times sufficient, considering you have at least one fairly comfortable test per round. Arcane Studies will give you a slight boost if needed, and Drawn to the Flame will handle high shroud values or necessity of instant success.

Enemy handling/Encounter managment:
Azure Flame and Shrivelling are your main damage dealing tools. Getting them early is crucial, as this is pretty much your only efficient way of dealing with enemies. 4 weapons combined with Arcane Initiate for spell searching will ensure you will pick at least one of them sooner than later. Be sure to carefully consider using the excess for your tests - if scenario is more enemy-oriented you will need those for replacement (I highly recommend keeping at least one as a backup). Blinding Light will help you evade enemies if needed, and Ward of Protection getting rid of Encounters that you don't feel comfortable to deal with.

Card draw:
This may be one of the weak points of this deck. This is mainly why so much card resource is put into Clues gathering and Enemy handling/Encounter managment areas. Getting key cards early on is crucial. Arcane Initiate will help you dig for spells. Crystal Pendulum is not the most reliable card drawing resource, but combined with Jacqueline ability might get some much needed triggers. Her ability itself might get you some draws as well (this actually happened to me more often than I anticipated during my Night of the Zealot run).

Economy:
Two Voice of Ra and single Emergency Cache proved to be enough. Consider spending your ability for Voice of Ra if possible, hitting couple of symbol tokens should set you up for the game. Robes of Endless Night will also make your spells a bit cheaper (on the top of making you more durable).

Other:
I was surprised how good Ritual Candles turned out to be. They are cheap, they are universal and Jacqueline ability might help get this +1 boost if needed (remember, discarded tokens does not count towards Candles ability - you actually need to choose token with proper symbol on it). Prescient is a handy skill that can bounce back used spells - really good for bringing Ward of Protection back, but can also help with other areas depending on situation. Defiance is a good test boost that will enhance your chances to succeed.

Mulligan targets:
Always keep Arbiter of Fates if you get it. Azure Flame, Shrivelling and Clairvoyance are your key assets that you really want to have early on. If you don't, consider keeping Arcane Initiate for a better chance of getting them early. Discard everything else. If you are lucky enough to get them all in the initial draw, focus on Ritual Candles or Robes of Endless Night next and feel free to feel good about your current run.

Final comments:
Jacqueline is very unique and fun to play investigator. I found her especially good for solo plays. Triggering her ability not only combos well with some of the cards (Ritual Candles, Crystal Pendulum, Voice of Ra, Defiance, Prescient) and mitigates the downside of others (Azure Flame, Clairvoyance, Shrivelling, Blinding Light) but also rises your chances of success once (or twice with Arbiter of Fates) per round. Having her cards and spells rely on Willpower will help you handle most of the challanges you face. Agility is her weak point. If you need evasion, hunt for Blinding Light, keep Ward of Protection for agility encounters. Other than that you should be covered in pretty much every other aspect and soon you'll realise she is a blast to play with ;). I tried several different versions of this deck and this is the one that I feel very comfortable with, I'll easily pick this one going blindly in any scenario or cycle.