Gardeners, horticulturists and plant keepers.

I'm in the beginning stages of exploring a business venture and I've got some questions about your growing preferences. What's the first thing you look at when choosing a potting soil/media/substrate? What are some big "no thank yous" when deciding? What are some big "yes pleases"? Do you grow fruits/veggies? Exotic? Decorative? Trees/shrubs? How much diversity do you see when choosing a potting material? Would you be interested in custom formulated growing media to mimic the natural habitat that your plants originally came from?

I hope, based on feedback here and asking around nurseries, I can find or even build a market for specific soils/media.