Carisab,
Congrats on the tads! Sound alike you are doing a great job with them! I do not have any experience with tads yet so I can not comment on the smaller one and what to do.
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I think your tank looks great! The only thing I would suggest you add is some Leaf liter (about .5 - 1" of it over the top of the substrate) which you have already mentioned . Also I would suggest you adding a culture of Springtails to the substrate. Springtails are little tiny insects that thrive in vivariums. They eat all manner of decaying/decomposing items and turn them into nutrients the plants can use. They will eat any dead leaves, frog waste, dead feeder insects, and more. You frogs will also snack on them from time to time. You will want to add the Springtails to the tank roughly a month before the frogs move in to give them time to breed and establish themselves in the tank.
As for the plants they all look good and healthy. You will want to make sure you have the right kind of lighting to encourage photosynthesis so your plants will thrive and grow. You want to provide around a light with around 6500K color. The type of light you use can greatly effect the humidity of the tank as well. Using the standard incandescent bulbs will dry out the air in the tank quickly and result in you needing to mist the tank more often which can lead to the soil becoming waterlogged and nasty. LED lights or Florescent bulbs are best anymore. They can provide the right color temp while producing little to no heat.
I can't see one in the pictures, but you will want a digital Thermometer and Hydrometer. Analog ones are very unreliable.