I would either keep it between 1/2 to 1 inch or 3-4 inches. If you keep it shallower, it is easier to stir and keep clean. Some go deeper to keep a true DSB for denitrification purposes. I personally would avoid anything in between.
That’s my preferred depth. I think what you have is a nice level. Plenty for sand dwellers to live. I keep some in an out of the way spot in my sump in a Tupperware. This way I get the benefit of the bacteria that colonize it and if I qt a fish that needs a sand bed I have extra without digging up my display.
Like @BighohoReef said, put your rock in first, then add sand. Unless you have sand sifting fish, then save the extra money on bags of sand, and go with 1.5 inches, you can always add more later, not easily but you can, and less means it is easy to remove if you decide bare bottom, and you also will not have a nutrient sink. Many pro's and con's either way.