For wallet security and security in general, perhaps a bitcoin operating system? Not a distribution with preinstalled bitcoin.

[outer]

If I understand correctly the bitcoin adresses are
Base58(Version+RIPEMD160(SHA256(PublicKey))+FirstFourBytes(SHA256(SHA256(Version+RIPEMD160(SHA256(PublicKey))))))

Since Base58 is easily invertible (just encoding and not encrytion) we can ignore the inner outer brackets.

Now if ECDSA is considered trusted, why hide public key with a hash?

Consider the following use case: a web shop owner decides to use a fixed Bitcoin adress. The first time he receives bitcoins nobody can determine the public key, let alone its private keys. Suppose the shopkeeper spends some Bitcoins, now the public key must be known publicly to verify the transaction. Now if the shopkeeper keeps making money on the same Bitcoin adress, the extra "layer of protection" is gone so that an entity if existant can crack ECDSA keys, can steal the money from this point on.

I try to understand bitcoin better, but from nearly all perspectives, it is just already implemented, without the design considerations being public.

Perhaps it was done for extra layer of protection for those who decide to never reuse the same adress (call them paranoids or just cautious netizens)
But that is still me speculating, a lot of bitcoins design decisions stay a complete mistery.

In the end nobody knows if backdoors were planted in any algorithms, or vulnerabilities are about to show up.

Among all the bitcoin doom scenarios, perhaps the most effective one from goverment standpoint would be to make sure to produce the first convincing p2p money system, only to pull the plug, buying time before the majority of citizens will ever try to trust such a system again.
If this theory is correct, they would pull the plug as soon as it has been the major mode of payment. This could generate a lifelong distrust with a lot of citizens.

Assuming this theory is correct what we actually have is a race: the goverment/organisation that built bitcoin to undermine or delay the arrival of real cryptocurrencies by undermining the credibility in this category of money, they want the bitcoin community to grow quickly (convince people of cryptocurrency) right in time before they pull the plug (cold shower of hard-knock reality lesson to crypto currency users). The people who actually believe in cryptocurrencies, must try to identify the built-in kill switch(es?) and adapt the code. How much time is left before the organisation decides to pull the plug?