Whilst i completely agree with your argument for decentralization, steem should stick to its roots and remain as a blogging/social media platform that is was built to be. I don't see Steem replacing banks and neither do i think it wise to shut your bank account and move all your money in to steem. Whilst its easy to get carried away and believe steem is the answer to all our problems and can be manifested in to many things it has its limitations. The solution the the worlds financial woes lies i blockchain technologies and i believe a service such as Ripple or NXT and maybe even Ethereum provide better solutions for this purpose.
Investing in a basket of cryptocurrencies right now is probably the right call, including steem ofcourse. Just like any other investment, investing in any technology requires knowledge in what drives it value. One of the most important things though is the people behind each of these ground breaking technologies, for example i believe much of ethereums value comes from not only the potential of Ether and its code but the belief in Vitalik to be the one to get us there. NXT and Ripple too have some very influential and dynamic people working on their respective platforms . At the end of the day "Any company is only as good as the people behind it"