I'm planning on getting another big tank

in the near future, and I'm trying to decide on who I want to live in it. My first choice would be a 36 gallon bowfront, but I need to do some measuring and planning - as well as make sure the floor is going to hold that much tank. I might have to downsize to a 29. How does this potential combo sound so far?
Dwarf rainbowfish and/or Celebes rainbowfish for schooling fish - how many and either/or would of course depend on what size tank I end up with (not to mention availability)
Red-tailed black shark - I know one only, but will they get along with other fish? I've always admired but never kept them
Weather and/or kuhli loaches - How many TBD, of course.
I know it's sketchy, but I'm in the beginning stages. I'm trying to plan this out for once instead of getting the tank and then deciding what I'm going to do with it. I'm trying to concentrate on fish I've never kept before. Depending on how my current experiments with planted mini-tanks go, I might try for at least some live plants as well. My green thumb so far doesn't seem to work with aquatic plants.