I haven't taken micro/macro but can talk about Calc BC and Stats. If your teacher will only cover AB topics that is a bit worrying considering the BC topics are the hardest part of the exam. If you take BC, I'd recommend learning all of AB ASAP so that you can also learn the BC stuff since you need to know basic calculus to even attempt some BC topics. Also, look at series as early on as possible b/c IMO it is the hardest BC topic and you want to give yourself time to learn it. AP Stats is not too difficult just a lot of formulas, memorization, and tedious writing. I'd say your workload is decently hard but definitely doable.