I think Waite's book is brilliant. It's horribly written but everything in it means something. I agree that there is no need to spend the next forty years trying to figure it all out, but it can be rewarding if you are really into the deck and want to understand where Waite was coming from in terms of Masonry, Mystery religions, alchemy and mysticism (among many others).
The Minor Arcana relate to specific Grail myths and the continuation of their spiritual objective in Masonry.
Several places in his Major Arcana text he makes specific reference to the Book of Tobit or Tobias, which is part of the Catholic Bible, as he found it particularly relevant to the cards. In fact, his GD magical motto, Sacramentum Regis, comes from this work: “For it is good to hide the secrets of a king, but honorable to reveal and confess the works of God.” Etenim sacramentum regis abscondere bonum est opera autem Dei revelare et confiteri honorificum est. (Tobias 12:7). What's more he uses this quote when talking about a work known as the Triumphal Chariot of Antimony—linking both the alchemical antimony and "the secrets of a king" to the Chariot card. Antimony is the key to why the Charioteer seems fused into his chariot: "“ANTIMONY, the type hard'ning metalloid . . . has a bluish white hue; 'Tis lustrous, brittle, and easy to fuse” (J. Carrington Sellars, Chemistianity).
Furthermore, “And Tobias went forward, and the dog followed him, and he lodged the first night by the river of Tigris” (Tobias 6:1). Notice the dog in this 15th century Italian painting of the subject:
http://en.wikipedia.org/wiki/Image:Filippino_Lippi_016.jpg
The Archangel Raphael, angel of healing came to Tobias and to Sarah with an image reminiscent of the RWS Lovers card: “At that time the prayers of them both were heard in the sight of the glory of the most high God. And the holy angel of the Lord, Raphael was sent to heal them both, whose prayers at one time were rehearsed in the sight of the Lord” (Tobias 3:24-25). Furthermore, Raphael tells Tobias how to rid his beloved Sarah of the devil Asmodeus [link between Lovers and Devil cards].
In reference to the World card, the Book of Tobias features a promise of a restored Jerusalem (who is sometimes depicted as a woman): “Jerusalem, . . . Bless the God eternal, that he may rebuild his tabernacle in thee. . . . Thou shalt shine with a glorious light: and all the ends of the earth shall worship thee. . . . blessed shall they be that shall build thee up. . . . My soul, bless thou the Lord, because the Lord our God hath delivered Jerusalem his city from all her troubles.” (Tobias 13:11-19)
These are just a few of the hidden treasures buried deep in Waite's book and a brief look at a few of the things he was thinking.