So, you are just connecting numbers from here and there and making that assumption that 2.625 is a good optimal investment size for BTC! is that what you are saying. If that's the case what will you do with the money which you still have in savings along with the 2.625 BTC. Will you not spend those fiat money to buy more BTC. Because the more BTC you will have the more profit or loss you could make.

Large investment = large Returns.