Quote from Traveler:
They call it a margin account but there's no real borrowing, hence no short sales, no reg t margin, no levered or short FX.
http://ibkb.interactivebrokers.com/article/188
You do not need all the stuff you mentioned. If you want leverage, trade futures. You can't short stocks, but you can certainly short stock index futures.
The beauty is that you do not have wait for T+3. So the funds are more efficient.
Also, faster to get lost in the market volatility....