0-25 is the Major Arcana (with some liberties already taken).  We could potentially do some based on the Minor Arcana, less powerful of course than the Major Arcana but strong nonetheless, like B-class to the Major's approximate A-class (note: some Majors exceed or fall beneath A-class, it's just a general baseline).  They could be fairly freeform combination, as long as the title follows the naming convention:

Ace/Page/Knight/Queen/King of Wands/Coins/Cups/Swords/Staves/Discs

And in accordance with the Arcana theming, Wands and Staves have something to do with Fire, Coins and Discs have Earth, Cups have Water and Swords have air.  I'd permit these being stretched of course.  To make things a little different from the Major Arcana, why don't we say that the Minors were chosen by the Majors for whatever reason and elevated to their positions.  Say, for instance:

[hider=Esau, Knight of Cups]
[img]http://orig05.deviantart.net/2435/f/2015/264/f/c/rathos_by_katemaxpaint-d9aevec.jpg[/img][/hider]
Current Holder: Esau (Crocodile), chosen by Numa, Temperence, for his ferocious willingness to protect those in need

Of course, anyone who wants can try this, but I don't expect many will.