There's a plot I made a year or two ago that I really liked, especially for a doable cyoa format. Before I begin, I once was a really good ssbb player back when I even played videogames. It was fun to annihilate my brothers and friends anyway (using some of the worst characters for true trolling). I also was fond of Fire Emblem Awakening even though I never actually played it.
Setting: some pocket dimension where the characters were all taken for a tournament to see who is the most powerful character. I'd have a supply of a bunch of colorful (and hopefully recognizable) characters. It'd be sort of meta because there's an unseen "audience" watching and betting on the characters, though they'd just be humans.
Thus, the storygame would follow the style of a tournament. Essentially, the protagonist (Lucina who's my favorite character to use in SSB4 and pretty interesting in my mind) will have to make her way through the tournament and win. It'd help with the plot because there's no way to change the lineup of who you'll face unless you loose, though there'd be some significant branching in between the fighting (making this a Branch-and-Bottleneck) ranging from wandering around the compound to attending a barbecue to pursuing a relationship with Robin. I even considered using CYS members' personalities for many of the characters.
I'd have some comedy in there, but there's always going to be that next next sitting there in a foreboding manner. Plus, Lucina was actually a pretty bad fighter in-game, so I can go all Rocky Balboa. Everybody knows it's impossible for her to win. The feel of the storygame would hopefully be "fun".
Hilariously, something irl can also be applied. She was originally one of the very worst of the SSB4 characters (though always said to be underrated by some the "best" players); however, game updates buffed her a great deal to make her one of the "better" characters. I could apply that in multiple ways in the game such as game updates occurring in between the individual tournaments.
For a year, this has been my default storygame to plan out but never one I ever went and wrote (beyond one instance where I wrote 4k words). The scope that I'd want to do and my inability to write good fighting scenes are keeping me from making it though... for now. This'd probably be a good entry to any Fac Fic contest we have here.