As a student it is always great to learn new things, I recommend developing a theme from scratch and buying a professional WordPress theme. In doing so, you can see the difference in the amount of work that goes into building a professional theme vs the built-in themes.
This will also allow you to possibly learn from it to increase your web development skills when you start building themes from scratch or eventually build your own professional themes and sell them. You will know the quality level you need to be able to reach in order to build sites that are at the professional grade level vs amateur and possibly make a nice income from doing so if you choose too.
This will also allow you to possibly learn from it to increase your web development skills when you start building themes from scratch or eventually build your own professional themes and sell them. You will know the quality level you need to be able to reach in order to build sites that are at the professional grade level vs amateur and possibly make a nice income from doing so if you choose too.