I agree with the Steph Curry style drills, too. Before I start ranked matches, I hit up training mode and don’t allow myself to play ranked until I got my BnB combo 20 times in a row without any error (error resets my count to 0). After that I start with casual matches and ranked, while still spending the time between matches in training mode to do all sort of combos, just the way I feel like at the moment.
The problem with dropping combos because of nervousness in ranked matches also comes from the fact that you are scared of losing. I found a good way, which helped me lose pretty much all nervousness during ranked. I don’t know, whether it helps for everyone, but it definitely did for me. This was back in USF4, I also noticed that I was more nervous when I played against people, who were better in terms of PP/BP. That’s why for every match, I looked away from the screen, when the player info was showing and I also ignored the info on the screen during the match. This way, you respect every opponent the same way and you are forced to look at the way the other player is fighting. It eliminates mistakes by respecting your opponent too much or too little. In addidition to this, I tried to play 100% defensive. This forced me to punish every unsafe jump-in or combo and I also had to give up the idea to win very early on, because it’s damn hard to win by only punishing without any aggression at all (I’m talking walking away from the opponent after a knock down, just to give the opponent more oppertunities to attack you). If you do this for a couple days, you are so comfortable with just doing nothing and waiting for your opponent to fuck something up and this will happen a lot.
A strong defense is really the best offense you can have and if you see your opponent running out of ideas on how to get in on you, you can just punish their mistakes easily, which leads to less combos being dropped.