We bought a specially recommended kind of organic disinfectant that is used to clean it once a month that causes no harm to the environment or indeed the baby.
You know thats an oxymoron right?
Just because its organic and not harmful to larger animals doesnt mean it doesnt destroy good soil bacteria (which encourages bad resistant ones to take over), and you cannot have a heathy eco system without that. It leaves insects and animals prone to nasty colonisations & disease. Encouraging birds and insects in other ways wont make up for the fact that without a key part of the ecosystem: healthy soil bacteria, super bugd and disease can spread within any insect/bird colonies you encourage and spreading it on to wider communities.
The fact that you say that there is no neighbouring soil makes it even worse.
No one is stopping you from doing what you want. But you cannot seriously believe that adding plastic and disinfectant to the outdoors isnt hatming the ecosystem!