You are wanting a short, shade and drought tolerant, grass like, tropical groundcover that will stand up to kid's soccer practice. Tough one. How about sand for the younger years and then plant something else when the kids are grown and have lost interest.

I agree the window needs nothing. Because I think this is a back door, because it seems this is a breakfast nook I would hang a huge family calendar/white board type. Not the most decorative but function is always my lean in, but it really depends on your situation and need.

I had a cat that loved to chase down grasshoppers. I wasn’t sure whether or not she ate them. :) I would start here: How to get rid of grasshoppers

Ortho's Get-A-Bug would eliminate any slugs. Rabbits don't eat hosta. They are damaged by the sun/lack of water. Hosta do not ever like full sun. Some can tolerate it if you water enough, but they would be the solid green 'blue' varieties. Never a variegated variety. The sedum you have there could be divided. Do you want a plant that is there year round or just during growing season like hosta are? I would go to the local nursery and get their suggestions. Hopefully they weren't the ones that steered you wrong on the hosta.