I have thought that one key advantage crypto (bitcoin, litecoin, Dash, monero etc.) has over gold is that its supply level is fixed and transparent, but can this or features make crypto more valuable than gold?
Crypto is valuable but I don't think that it would be more valuable than gold. Remember it is only a technology and technology become obsolete in due time. We can see where it can outshine gold but I believe that it won't out last the valuability of gold. In short in can be more valuable than gold in certain point of history and diminish but gold will always remain valuable in eternity.