(I know Queex has a whole load of house rules both in and out of his excellent supplement)
One of the ones I tend to do comes from the fact that most of the time I only get to run the game with 1-3 players (yeah, Feng Shui can work 1 on 1...).
Basically I add between +1-+3 for really good stunt descriptions (with +3 being a gigantic rarity).
Mainly this is to encourage really good descriptions from players and to get them involved, especially if they've never played anything like Feng Shui before - the other reason is when I do play one on one it allows my one player to be able to take on near as many mooks as I'd throw at three people.
I clarified the very grey passive/active doge/parry rule combo into a normal passive defense / active defense (as a defensive action), the characters can raise non chi attributes with an attuned site and I dodged the clunky sorcery combination rules. Some other minor adjustments, but nothing really special. For FS I prefer a rule light way of playing/mastering, for that the power of creative fantasy may run wild on a roaring rampage of revenge.
Currently I am experimenting with some mook rules for mass combat / easier mass mook handling, but until now I did not find any really satisfying.
I would suggest for adrenaline skills: combat skills, but even social skills in high stake situations or or tech skills like hacking with fix it under pressure.
Female: "Hey, 5 sec until the a-bomb goes off, you didnĀ“t even scratched the firewall and you are bleeding to death"
Male: "Yeah I know I look totally hot ... now put on the little black nothing ..." rolling fix-it and seduction
I was wondering if there's any official rule for extra damage from called shots for named characters and where it is, or if someone's got some good house rule for it. -1 - -3 AV for example as a stunt that if hits as a called shot doing +1 - +3 to your outcome or something (maybe that's not worth it I don't know...).
It it's a cool stunt, including a called shot, I take the opinion that it would be a shame to waste it. If the roll hits, I let the result stand as normal. If it misses, I consider coming up with an off-the-cuff reason to reduce the target's dodge by just enough to turn it into a hit with an Outcome of 0 or 1. This stops cool descriptions from being wasted without worrying about throwing off the balance or having players try too hard to come up with bonus-worthy stunts.