[is74]

A degree in mathematics requires a very large amount of effort and discipline, especially given your other obligations. Is this effort best spent on a mathematics degree, or maybe you could spend this effort differently and get what you want faster?

While point a) is a good reason to get a mathematics degree, points b) and c) are not. For point b), machine learning and statistics are much more appropriate than mathematics, and for point c), it is worth knowing that machine learning requires a fairly small subset of the mathematics you'd learn in a math degree. For example, a math degree covers many areas of mathematics (such as a heavy focus on proofs, abstract algebra, complex analysis and topology) that have no bearing on statistics and on practical machine learning. Conversely, a math degree also does not focus on statistics and probability, which are essential for data analysis.

Thus were I in your shoes, I would only study the math that is necessary to understand statistics and machine learning, and would start taking a machine learning course. The only math you need is multivariate calculus, linear algebra, and probability.