Based on the current problems of bitcoin, I would have the following features.

1.  No mining or staking.  Every second, all outstanding transactions are bundled into non related groups (sharding) and a small amount (from the fees) is paid to a random miner for each "group".  Firstly speeds up transactions, secondly takes out the centralisation (of big mining pools) and thirdly as you only get a dollars worth it is not worth pooling or asics. 
2.  Fixed % fee based on what you spend paid into a pool.
3.  Optional privacy mixer built in.  Incurs 2*fee.
4.  Some sort of (optionally) identifier built into the public key.  FredBloggs_j3hg12jh3gjhg3j12g31j3gj12h or hacker33_kj4hk4hkjhkj3h4kjh4k3j. 
5.  Still non reversible.

Just speculating here.  Any comments?