I think 3 majors are the max you can do, and you probably need to be in a combined degree for that.
I am not sure about the bio/chem side of things. For stats, I reckon you should try out the semster 1 course and see if you like it. I had an awful 1st year stats course as well. But my 2nd year lecturers were absolutely fabulous (unfortunately both of them are retiring). The materials are really interesting too, especially the advanced class. It moves away from the boring data analysis bit, and focus more on mathematical rigor. And you get a lot more individual attention as well, since there are less than 20 ppl in the advanced class.
One year ago I only intended to do one 2nd year stats course and one more in 3rd year. But now I am going to do a full major in stats. There is a national shortage of statisticians, the biotech sector needs ppl to analyse the massive amount of data, but very few ppl can do the job right now. So there is high demand in there.
