Redoing my bachelor’s degree for general specialisation and better GPA
If you were living in the same circumstances, what would you do? 


If I were you, I would do a part-time Master's degree in Computer Science while working on a not-so-high salary job.

You will waste your money and time by doing another Bachelor's degree in Computer Science. You won't gain too much. The courses are about the same except a few theory courses (depending on the program and school). At the end you still only have a Bachelor's degree.

If you do a Master's degree in Computer Science, the school will teach you more theories, more skills and you get a Master's degree at the end which can earn you more respect that you need when you look for a high-salary job.