I would second @VickiSoCal here; Post-AP/DE classes are meant for kids who are already at that level with ease. So for math, if you’re on track to take Precalculus in junior year, I wouldn’t necessarily aim for DE just yet. Seeing that you’re not on the usual track for kids who do take DE Linear Algebra/Calc III, you might not need to push yourself unnecessarily to get to that option.
I’m only a sophomore this year, but I will be taking a class with a Linear Algebra component in it next year. So unfortunately I cannot speak for its difficulty just yet; but I’m assuming it will be harder (or similar) to Calculus BC in rigor and material depth.
Four post-AP courses in your senior year sounds extremely difficult, and not of much use if you have to exert too much effort to get to them. Why do you think four DE classes will give you more time to work on the college admissions process? If that’s the regular courseload for college freshmen at the college you’re taking these classes at, I would assume that they require as much, if not more, dedication than a full high school timetable.
I would suggest you to take AP Statistics, or look into Calculus AB then BC, if you’re not sure about the difficulty levels, seeing as you’re in Algebra II now (right?). Or look into taking Precalculus junior year then do BC senior year — don’t stress yourself about the DE ‘labeling’ too much if you’re not at that point yet!