All watch cases I see in the media are hard ones. Anywhere can find TPU or Silicon ones, if at all they are available? And also screen protectors.

Would appreciate any inputs.

Machine, switch got a lot to choose from.
Avoid those cheap 1. The feel totally different.
Avoid those with quick release button.
Machine,switch.
For casing, if you always go for a swim with your watch avoid put casing on cause you have to take out to clean those water trapped inside.
For screen protector i use flex type. I use this https://s.lazada.com.my/s.fNVP2. Very clear

For casing i use spigen 1 abit bulky

I alway hit here there with my watch and i got kids , so i go with bulky case. I have a few case most are half snap on case. Easy to change. So far my flex SP are good. I go for swim time i took off the case the SP still ok.

My sp so far ok cause i have case on.

If you are careful kind of people then u can go bare or go for a transparent skin+ a SP.

One more thing, i would say avoid those casing comes with tempered glass. To me those tempered glass get scratches easily. Best is go with bare case/bumper + a flex SP