Ninjatrader margin is $286 for M6E.
Futures are regulated, forex not. I would go for futures, as Forex quotes are manipulated by many brokers as they take the other side. I traded forex years ago. They cheat with the pips as they know your position.
1-Currency position is just a hedge so won't be opening/closing regularly.
2-Risk is with the broker, not the market. IBKR has a $22B market cap and $232B AUM. Not a big concern IMO.

