I have 4 Amazonica in a 45x45x60. They went in as 0.0.4 but I think I've been lucky to get 2.2.0. I've clicked the other mentioned threads to read after this, but my experience is that 45x45x60 is about right for what I have and that well planted will enable you to see the frogs more (it's weirdly counter intuitive). Ours are quite shy unless they are breading and I really like that you have to hunt for them when looking at the tank.
Tankwise, this is what mine looks like now (in need of some trimming) and little things I've done through learning with them was to reduce the floor space. They never went on the floor so I laid a ledge across the left which is above floor level so I could have more brows in the front space. If I were to build again I wouldn't change much, maybe a few more meandering branches from right to left as the very front doesn't use much of the near glass space. That however was deliberate in my case as I was worried about the speed of the frogs and wanting them to be away from the glass when opening the doors.
Theres also a really intricate exo vine that I moulded and substrated into the back right corner to look like a tree trunk, which I was really proud of and looked amazing until about 3 week after planting when everything grew into it and now its too dark to even see!
Ignore the little pool, that is because I'm playing with reducing humidity for a period to slow breading down. I was looking to see how quickly the plastic pool evaporated. Normally its just leaves down there.
Here is how it started life for comparison before the frogs and leaf litter were added.