I took the soft plywood out and put in diamond plate only. Couldnt be happier.
I had carpeted plywood and it was hard to keep clean, fish blood made it stink, it held a lot of water making the boat heavy.
I put no underlayment under the plywood and it is not soft, though your support could be different. I dont think it is slippery though I have had others tell me it was
I like it.