I'm diggin everything except for the peat. That's organic right? Gonna break down into little clouds of ammonia, which may or may not be a problem if there is good filtration. I think I'm going to try to stick with non-plant matter, which is why I use Controsoil (Brightwell in USA i found out) I like that sea shell idea. This is great stuff in this thread.
While I agree with that, I think that can be accomplished with any substrate. I also fully believe that you can keep shrimp in bare bottom tanks if you have enough surface area (plants, driftwood, filters, etc...) to keep beneficial bacteria on/in.