You always know the perfect things to say

I really wish I was quicker and better with words, some people are so witty and say the most amazing things at the right time, I clearly do not. I'm a flustery person and half the time I can't even get what I'm trying to say out! This weekend I said something somewhat quick, but it was probably the meaniest thing I've ever said. I guess alcohol does that! My point is, I really wish I could say the right thing in the moment, whether it be flirty and saucy or bitchy and mean. I'm the type of person who always thinks of the perfect thing to say right after - when it wouldn't even apply anymore.
I'm thinking of You've Got Mail right now, when Meg Ryan talks about how she doesn't ever say or know what to say and she thinks of it afterwards, except for this one instance where she says the perfect thing in retort, of course it ends up being bitch and she regrets it. I'm not one for living with regret though, so meh!
There are just sometimes I'm having a conversation with someone and I could say the funniest or flirtiest thing but it doesn't come to me until afterwards, instead I kind of studder around it. It always happens when I'm in a fight to, right after the fight I think "why the heck did I not say that, it would have been perfect." Or I'll be talking to friends and they'll just say I should have said this, or that, and then I start thinking "that's so easy, why did I not think of that!!" It drives me crazy actually! I need to be quicker on my toes!