The OP ain't a trader so he will not be bother about this short volatilities happening in a period of 24hrs. He is trying to save money for long term. He did even mentioned he time deposited his money in the bank. So, what better option you give?
Because I personally think the OP is doing the right thing. Making half of his money deposited from the bank and the other half to invest and save to Bitcoin for a bigger profit than banks.
Even if his money rose by 100%, that doesn't change the fact that crypto currency or I'd rather say 'Bitcoin' is volatile. Volatility is sure. The price going up or down is volatility. You may say that the chances of things going wrong have reduced, doesn't mean shit can't happen. I hope you understand my point of view.