I think the key is what kind of major you choose to study for a double degree. I don't know much about your biology major. I think you must have a good understanding of it yourself, that is, what do you think your current professional knowledge lacks most, so you can minor in other majors. There is also what you want to do in the future and how to arrange your career path. For example, biology, you may want to do technology or research and development at first, but you still want to do management in the end, then you can also learn management or something.
Studying a double degree is to make your knowledge more comprehensive. I don't think we can simply compare with graduate students. At present, many good colleges and universities have set up a double-degree level between undergraduate and graduate students, and the salary is different from that of pure undergraduates, which is a little higher. Of course, if you want to take the postgraduate entrance examination without taking this major, you can actually skip it. If you take this major, you can take a major very different from yourself, and people's thinking will be different. But only if you have so much time, because it still takes some time to study for a double degree.
I think the most important thing is what your plan is for yourself and why you consider taking a double degree. It's not that the double degree of Hubei University is not good. Why not? No matter how bad it is, it is also a book. In fact, as long as you can do it yourself, it's better than having only one degree. This is because I am a graduate this year and have a deep understanding of finding a job. I think it is mainly my own reason that I can't learn physics and management well on the first floor. Maybe that person is not suitable for management at all. People who study management have many personal qualities, and the requirements of employers are relatively more than those of science and engineering. After all, there are too many talents.
Think for yourself first. Of course it works. The question is whether it suits you. Come on, I believe you will succeed!