3. Having to store coins "under the mattress" is a step backwards.
i'm going to be honest i've not idea what you are talking about? but you could be referring to a theory I proposed which i've called the "use/collapse" paradox , where because mining monopoly in Bitcoin creates price manipulation if the manipulators "use" the entity (Bitcoin) this will cause the market to "price collapse" (Bitcoin) so this causes it to be in effect "kept under the mattress "
lets explain:
Quark is fully distributed except for the EQ reward, this gives benefits (many) and causes some perceived problems the benefits far outweigh the issues as Quark is priced by the market and moving forward will be used and utilized by the market.
As a use case, how will grandma store her QarkCoins? Does she have to print private keys on paper, on a computer disconnected from the Internet, and with several separate copies that later must be put together? That's worse than even money under the mattress! Or does she need a hardware wallet, that needs to be backed up in case of hardware failure? In which case, we are back to square one again with private keys on paper or stored on a hard drive disconnected from the Internet. Extremely cumbersome management.
There is some wallet that uses a 12 word pass phrase or something like that, and then generates private keys with a deterministic algorithm. But would grandma try to remember the whole pass phrase or write it down on paper?