I have found larger fish (4-5"+) to feel very unsafe in shallow water <12". They seem to dart around the tank very erratically.
Personal bias I would do hillstream tank with boulders and algae with different loaches and 2-3 schools of minnows/rasboras/barbs that fit the bill but stay small.
I do also like the idea of that N. Amer. stream tank. Rainbow shiners and the like although I have struggled with them in general especially given our heat in summer.
Another interesting tank could be a long gentle sloping river bank tank with emersed plants one side sloping down to some aquatic plants and ending in the pool on the other side with lilies or floating plants mainly. This could make for an interesting environment for different species with different niches to go about their business.
G1 level rudimentary diagram

Personal bias I would do hillstream tank with boulders and algae with different loaches and 2-3 schools of minnows/rasboras/barbs that fit the bill but stay small.
I do also like the idea of that N. Amer. stream tank. Rainbow shiners and the like although I have struggled with them in general especially given our heat in summer.
Another interesting tank could be a long gentle sloping river bank tank with emersed plants one side sloping down to some aquatic plants and ending in the pool on the other side with lilies or floating plants mainly. This could make for an interesting environment for different species with different niches to go about their business.
G1 level rudimentary diagram
