I have a general idea for a new stack community but the idea is not yet well formed or defined enough to make a proposal. Where should this idea be discussed, Area51, MetaSE, or some other place? Discussion about how to bound the subject for best impact and distinguish it from the nearest existing communities, and which category does it best fit?
For a more concrete example: there is a "Life/Arts" category site for "Gardening & Landscaping" and a "Science" category site for "Biology". This leaves a very large space between "how to construct a raised bed" and "determining the effect of a specific enzymatic pathway for hormone synthesis in meristematic tissues".
A topic gap where you might find agriculture, horticulture, soil science(mechanical and chemical), and applied botany like plant breeding, (amateur and professional), which seem like they would dilute the pure science aspect of Biology site and while being well outside the scope of garden and landscape maintenance.