So! This is very much a work in progress: I might do a set of icons, as I don't really have the time or ambition to do an entire deck, or I just might make card-sized images. I've been tossing around the notion of reworking the Major Arcana of the tarot using Gormenghastian images, either from the mini-series or from Peake's own character illustrations. Behind the cut, you'll find the start of a list I made, with the names of the cards and the possible images. I got stuck on a few, so if someone would like to offer a suggestion, they're free to do so!
Note: I'm going by the numbering used in the Rider-Waite deck, ie. the one that most people think of someone says "tarot", as it's the most widely used next to the Marsailles deck, and the one that has influenced a lot of the modern decks.
0 The Fool -- Titus Groan, or Steerpike (since the Major Arcana tends to take the form of a Hero's Journey, and said journey is more or less divided between the two, in the books)
1 The Magician -- Dr. Prunesquallor
2 The High Priestess -- Nannie Slagg
3 The Empress -- Countess Gertrude (Natch)
4 The Emperor -- Lord Sepulchrave (Natch, again)
5 The Hierophant -- Sourdust/Barquentine (or the telescoped version from the BBC miniseries)
6 The Lovers -- Titus and the Thing/the Wild Girl *OR* Bellgrove and Irma Prunesquallor
7 The Chariot -- Titus's boat (or it could be Muzzlehatch's crazy car, if I could find a drawing of the damn thing)
8 Justice -- Bellgrove
9 The Hermit -- Mister Flay, post-banishment
10 Wheel of Fortune -- ??
11 Strength -- ??
12 The Hanged Man -- ??
13 Death -- older!Steerpike
14 Temperance -- ??
15 The Devil -- Swelter (which fits a little too well, IMNSHO)
16 The Tower -- The Tower of Flints or the burning of the library
17 The Star -- The Thing/The Wild Girl
18 The Moon -- The Twins, Clarice and Cora (The card is associated with duality and lunacy, so it seemed a good match)
19 The Sun -- Fuschia
20 Judgment -- The Ceremony of the Bright Carvings
21 The World -- Steerpike perched on the rooftop/Titus riding off into the sunrise