Aren't you at all interested in managing your capital gains exposure? Short term trades tend to play to the advantage of the broker (fees) and tax collector (short term cap gains tax)
2) Broker fees are $0 as I use Robinhood.
Like I said, I made a ~44% return. If a $7 trader fee is your argument for it not being viable then you are most likely not investing enough money, or not getting a decent return.
...and if your business is really killing it, and you're also killing it in the stock market, I am certain you won't have a problem paying a few dollars to the US Gov. It's still better than other investment avenues :-)