Standard height is usually 75- 78" for a regular shower head. Rainshower heads usually go higher since they have good water coverage usually 80-85" or from the ceiling.

I’d like to see any waterproofing details. Which don’t exist, as someone just plopped lumber down over an existing floor to create this shower. And then installed done rubber. with no preslope. It hasn’t even begun, and it’s failed. Badly failed. Expensively badly failed.

I can plainly see slope on the floor.

Only on the right hand side. And it’s more than 1/4”’per foot. Having extra slope in one area doesn’t make up for no slope in some areas. Or completely wrong construction and waterproofing.

Go a little higher.