I never understood why more people don't play Sonya. Within minutes of picking her up back in May I was like holy fuck. Especially since I mained Scorpion up until then. It was like how a baseball bat feels after you take the donut weights off of it.
But yeah...why don't more people play Sonya at high level? There are only a small handful of people you see using her at tournaments, despite her being such an unbelievable character without many bad matchups, and even in those matchups she can hold her own.
One thing I'd throw into the punish section is a D4 against Sektor's teleport uppercut (regular and EX) will go through it, and the teleport will come out on the other side with a total whiff, leaving him wide open for a big punish.
This works with most characters vs. Sektor, but is particularly effective with Sonya.
I'm sure it's nothing Sonya players don't already know, but spamming D4 pressure and mixing F4 into it seems to be pretty effective too since the opponent is usually going to stay blocking low, which sets up more easy pressure when the overhead hits.