I'd go for Computer Science, I suspect that you will mainly doing things like Feasibility Study for a Software Engineering, which IMO isn't technical enough for me, but then again, neither is CS, that's why Maths > all.

Refer to http://www.cs.utexas.edu/~sahilt/research/SEMyths.html for some insights

When I first started college I didn't know which degree to go for either, and the school didn't make much of an effort to tell you the difference. The first two years were pretty much the same classes. Then it became apparent that I would have to choose. I liked the CS degree because of its freedom, and I could take the classes that interested me. But the SE degree courses were important to me too, because in the end, I do want to create large-scale software applications. This summer I found a degree that was a good compromise and allows me to finish school in 4 years, taking the classes I wanted to, but still getting a strong foundation in software engineering. It was Computer Science with a concentration in Software Engineering. Look for that. For me it proves to be quite flexible.