I'm still learning heihachi but if you go into stance on block you can stance cancel with df,b. I think it's fast enough to save you if you find yourself in that situation.
it is not. all of the details of that stance are written in the description of the main video. that cancel takes 9f, meaning most of your attacks on block are -11 into stance.
It's a long list. Leo was just about ready when Lidia came around so that might be next. I still have a lot to learn about Reina, but I really want to do that one. many other characters I'd have to learn with everything that's new. Lee is possible, but like I said, it's a long list. :)