I could see why you would want to go for the Knee Bash in that situation, but I would use the sweep. This is purely as a punishment combo, and so I would choose to do damage and get the knockdown, allowing me to throw a Jab Hadou to move forward and dictate the pace of the match. I tend to try to land the Knee Bash after a knock down, using meaty jump jab XX hurricane, and then varying between knee bash, short X2 to super or a dragon. But it’s personal prefference really.
As for Juice Kick then Shoryu Reppa, do you mean using the Juice kick as a cross-up or to evade a fireball? As a cross-up I would say no, you should always do short X 2 first to confirm it. However in other situations, like as I said to evade a fireball, then maybe, as your opponent may expect a Knee Bash. Still I think it’s safer to use a Dragon instead and save the Super for when you know you can connect it guaranteed.
Oh yeah I just thought of one other M.Tsun trick. If often does cr,short, stand short X jab dragon. You can use that as a hit confirm when you don’t have Super. Just be careful because quite often the funky kick comes out by mistake.