H'okay so!
I have no idea when the Card Game started - definitely before 2008, possibly as far back as 2005. There were only ever 5 Generations, and the rules changed dramatically for Gen 5, largely because the previous rules were awful.
Frankly I think the current rules are awful too, but people will keep insisting they're playable. (I don't think anyone has accused them of being fun, though.) They were very much written around the existing cards.
The page for the card game is here, and yeah, Photobucket hates me now; I can't open the folders (it forces me to log in and then tells me I need to pay or they'll delete everything). I've just copied the Card Pack Generator across to the Neocities site, and it seems to work okay; the cards it gives you have a Photobucket watermark on them, but if you open them in new tabs they come out clean. Failing that, the Crashing Down Theme Deck is a PDF and should definitely work.
I don't think there's any good reason to make a Gen 6. The biggest issue with the game is that the cards are two specialised - there's no reason for an Agent player to ever play a Canon, and no reason for a Badfic player to ever play a Canon except directly on top of their own Badfic, to be immediately Ensnared. There are so many monsters and locations that the odds of actually being able to play even one Monster card are really low - and why would anyone deliberately walk into a Monster anyway? Not to mention that if there's no Crossover card in play, it's entirely possible for the players to get stuck in entirely separate canons with no way to get to each other!
In the older rules, I think the Locations were played as a grid, and you could travel to adjacent ones. At the time I thought that was unwieldy, but it might be best to go back to it; maybe you have a separate Worldbuilding phase at the beginning of the game, where players take turns to place Locations until they fill out a grid (4x4 maybe?). Then it's almost like a boardgame, where you can move around in specific ways and strategically block paths with Monsters. Still can't find a good use for Canons though, other than literally feeding your own Suvian.
hS, always easy to nerd-snipe