Spigen Thin Fit Pro Protective Steam Deck LCD (2022) / OLED (2023) Case with Kickstand TPU & PC Cover with Shock-Absorption Anti-Scratch Cover - Black

I use the Spigen Thin Fit Pro. I like it because it is thin and light enough to not add much extra weight and still fit in docks but offers additional drop protection (along with a screen protector). obviously it's not going to do much for something like leaving the Deck on top of the car and driving away or a fall onto the corner of a table right on the screen or something, but it is extra protection without sacrificing much in the way of weight and button/slot accessibility. Your appears similar, though almost twice the weight.

this is quite slim and still fits in the OG carry case, dont have the valve dock but use a different 3rd party dock and it fits in that np. recently however i swapped to this fitted dock and swapped to this grip case which still lets me clip the dock to it.