The combo I usually go for is Ermac's telekinetic bounce, jump kick, teleport, dash, backpunch, backpunch, telekinetic choke, does 30 something percent and is fairly easy. And almost everyone I've played has just been jumping all over the place, so that initial special move is easy to land.
I did take the piss a bit after a few of these messages, one guy I just dashed in and sweeped, managed that about 5 times before he blocked low. Another Mileena I just pinned in the corner and did telekinetic choke as she woke up and they had no answer to it. It's not that the players aren't great, it's just that they have no desire to learn, and if you win through tactics that they can't copy or easily beat, they flip out and get abusive.
And to those that agree with the "You spam, therefore you aren't playing properly" philosophy. You're pretty ignorant, I got a game with a few people who were actually bright enough to block my combo starting specials, and funnily enough, my strategy became a bit more complex, it was refreshing. I had to think! They didn't throw out unsafe moves for no reason, they did combo's, they didn't waste their x-ray the second they got it.
Point is, if somebody beats you with a repetitive strategy. Realise that it's repetitive, and beat it. Rock paper scissors, no one move is unbeatable.