No worries about growing zone, weather, space requirements just your dream garden.
I would love to be able to grow vanilla, they look really cool the flowers smell amazing and having a source of fresh vanilla beans would probably unlock some next level cooking. An olive tree would be cool too, I can eat unlimited olives and making my own oil would be awesome.
It likes really well draining soil so as little clay as possible and definitely should add sand. Its also like mediterranean herbs in that it doesn’t like a lot of nutrients so go low on adding any compost or fertilizer. I know it prefers slightly alkaline soil but I haven’t really noticed it be to picky. Basicly it grows in the oppisit conditions of tomatoes, if you’re tomatoes are doing great in it your lavender needs to be planted somewhere else.