Danger

I'll take that risk

Get shower floor mats that grip and its all g

Don't bother with suction cup sexytime handles, I've heard they don't work too well.
Get temporary bath safety bars. Their meant to have someone's weight put on them and are designed accordingly. With the added bonus that more than one hand can grab them at once.

Idk man, the benefits outweigh the risks.

It also just takes to fucking long to be standing the whole time.
Bathtub sex is where its at.