2 small things:

a) maybe mention that Polkadot’s ICO funds were not really hacked but lost due to a bug in the parity wallet implementation developed by Gavin Wood.

b) On mentioning Ethereum, EOS, ZCash, Monero and Cardano one could also mention Cosmos, a network that is about to launch in 1 month and that comes closest to Polkadot in terms of what it wants to achieve. Still Polkadot’s scope is broader but Cosmos also goes for interoperability and horizontal scaling.