Building another business while accumulating your Bitcoin is not a bad idea, and is very much possible, let's all stop seeing Bitcoin as a source of income because it may cause panic when ever there's a dip or fall in Bitcoin.
Economist will always advice against having only one source of income but if you are just starting to build your financial status, it's better you start with what you are more comfortable with. Some people choose Bitcoin because they have a better understanding about it and some choose to open a business first. Which ever ways, i don't think there's anyone that's not profitable as long as you have a knowledge about it. But after you have made enough money from your first start, you can invest in other things.