So, I'm working on a mash-up of a micro card game and a legacy-style game. Stay with me here. It's an odd combination.
The base game is a small deck of cards that you play through once. You score. Then you mark up the cards with stickers. Maybe you get to rip up some cards. At some point, when the deck gets low, you replenish the deck with a new subset of fresh, unmarked cards. Rinse and repeat.
Ultimately, the fun of the game is manipulating the deck and cards to the player's whims. Claiming ownership of certain cards, and figuring out ways to destroy the powerful cards that other players have claimed and built. Every time you play the deck will be somewhat different, based on how you've manipulated the deck and cards.
As far as what the stickers and "write-on-the-cards" kind of thing do, I think that's fairly easy to come up with stuff. It's mostly just giving the players some weird ways to control the game a little bit. And trying to come up with bizarre ways to combo stuff.
But I don't think that's the BIG issue that needs to be solved.
I think the real trick is figuring out the pacing of mucking up the cards and deck. Ideally, you want the ability to enhance or destroy a card to be a relatively special event...so a single player shouldn't be able to do it every game. Maybe every third game, on average? Every fifth game might be too far out. Or maybe not, depending on how fast the game itself is....these little micro-games play pretty darn fast.