I see you joined us in March, and as I don';t think I've yet welcomed you...Welcome to Tropical Fish Keeping forum.
My particular area of interest in the Amazon, and I've had Amazon-themed aquaria for over 20 years, so this is right down my street.
First question is, just how authentic do you want this? Strict biotope tanks have all plants and fish species, plus the decor, from a specific stream or lake. Moving on to geographic tanks, which is what I tend to favour, all the fish and plants and decor are from the general area, though not necessarily the exact same watercourse. Check the photos of my 115g Amazon Riverscape and the 70g Flooded Amazon Forest tanks under the "Aquariums" tab below my name on the left to see what I'm currently running. All fish and plants in these tanks are native to tropical South America, and the substrate is play sand which in appearance is identical to the sand in most Amazonian streams. And the chunks of wood are authentic.
You mentioned soil substrate; have you had this before? I personally do not recommend soil due to the issues. Plants don't need it, as my tanks illustrate (plain sand substrates).
I would leave out the artificial plants, as they tend to look artificial especially when live plants are included. And there is a great benefit to live plants. At this point, you can go one of two ways. Plant the tank, as shown in my photos, or go with a plant-less substrate tank using only lots of wood, and have floating plants as the "planting." We can discuss these options further if you like.
On the fish, I would avoid angelfish in a 29g. This is a shoaling fish, living in groups, and is best as such in a 4-foot or larger tank. A mated pair can manage in a 29g, but that is going down a very different road than a display tank which I think is what you're wanting. At this point, I'll mention our profiles section, second heading from the left in the blue bar across the top of the page; each profile has info on numbers for the species, tank sizes, compatibility issues, etc. If the name is used in a post exactly as in the profile, it shades to form a link, example Pterophyllum scalare for the common angel. We have plants too. Check Java Fern and you'll see this is a SE Asian species, though that doesn't matter if you don't intend staying in the Amazon with the plants.
There are so many fish from the Amazon, but some will be wild caught and this brings up the question of your source water parameters. Do you know the GH (general hardness) and pH of your source (presumably tap) water? Knowing this will help us narrow down possible fish species. I have, or have had, almost all the South American fish in our profiles.