I don't know anything about getting out of ZSS' grab release, I hope someone could answer that, it would be **** helpful.
And Popertop, that's some great advice, I happen to fall in those bad habits to, like I once had this stupid habit of constantly pressing L while trying to TDI. It was so annoying, but I did what you mentioned and it stopped. So duffman, do it, it will help you.
Now for my question of the day, up to what percent does nair to bite work till? Like if the opponent is at 40%, would it still work? I find that to be a great approach, most of the times they will be waiting for the fsmash.