AND
In my opinion, these are your strongest reasons to trade the ASX if you are going to be living back in Australia. Put simply, you are going to have to be at your screens all night due to the style you trade - unless you only decide to trade for a specific block of the US trading day e.g. first 2 hours.
If you have a fiancé/wife, kids etc, is it going to be sustainable to be scalping US markets in the Australian time zone?
I don't trade US equities, but there are companies like
Stake. You can find pricing information
here.
@tech/a also speaks highly of Interactive Brokers. Pricing information
here. I'm not sure about the tiered or fixed pricing structures. Maybe some who uses IB can elaborate on that.