High on my wish list is a zorro connection for the DeGiro.

DeGiro has for the european stock and ETF market better conditions than IB.
The main issue with trading the US market is the exchange rate risk which is currently indeed, at least temporarily, chewing up any income you generate with Z9 or other conservative strategies one may run. Therefore the addition of a DeGiro API would be excellent to the tap european market and benefit from the lower costs. THis seems feasible:
https://github.com/pladaria/degiro