To be frank, both should be good depending on how you trade.
If you are beginner or looking for something simple, then MT4 is perfect. If you need more advanced features, cTrader most probably is better choice.
Most of the brokers that I know offer micro lot size only. And to be frank, I think there is not much difference between micro and nano lot size, even if you are a beginner yourself. Many brokers like turnkey forex, fxchoice, etc offer micro lots, so you can try them out.
I have never experienced them but from what I can see is that their liquidity are quick lacking which in turn making the volatility quite high, so this is what is setting me back from giving them a try
Check offshore brokers like turnkey forex, lmfx, tradersway. All have high leverage options. But would recommend you to be rational with using your leverage; high leverage got quite many risks attached to it.
Do not rush with earning quickly. Go slow.
It is always better to aim for consistency while you trade. Forex has a lot to offer, yes you can earn well but be rational with your choices, not greedy.