Been playing the game for about quite sometime now,since it came out in my country 2 days after the japanese release.
First of all,I'd like to address the far away mixup issue.Basically,5DD 4DD Sickle Storm is a very risky choice to use nowadays,because Sickle Storm comes out really slowly,and anyone with experience would be able to avoid it,without crushing any primers.
Secondly,would be Zwei C.Yes,basically it is safe in most cases.Because after Zwei C you can backdash,IAD,or stay on the spot for a counter hit.However,there are still dire consequences when predicted.Jin can use his 2D for people IAD-ing,resulting in a counter hit.People can still IAD after you to punish you.
And no,it is not coincidence that people get poked out of Zwei C.If Zwei C is expected,they can be counter thrown,mashed out of it,as well as get a 6AB.
She cannot RC out of Crescent Saber into 6C/5D.However,on low Crescent Sabers,she can RC into j2DD 2DD 6C Zwei C.
Together with my friends we managed to find a legit 4.5k counter hit combo for lambda.Dont get too happy now,because there're specific requirements for it.
Basically after a Zwei C,you 66 into 5C>6C, you have to be around 3 character's width away from the corner.Repeat 5C>6C for 2 more times and end it with an air combo or Calamity Blade.
Hope I've provided some help here.Cheers from Singapore.