Quite extensive article. I would add Dai backed by makerdao as an algoritmic stablecoin.
About digital gold. We need to see of the investor is looking at being pegged to USD or gold. Gold is deflationary and cod look as the best solution. I am anyway wondering if, long term, bitcoin itself will not play that role. With a long term perspective swing in price could be tolerated and they should reduce in future. Fiat backup would make sense not to be affected in daily life (in this case gold is not necessary always the right choice). I also dont rule out some utility token to reach a scale so big to find a kind of stability to replace the need of fiat: bat looks the best candidate. I have discussed it here bat equilibrium