I have the same issue, especially on my back. I can tell it's hormone related, because I notice the fluctuations with my cycle.
You don't say what kind of birth control you use, but there are some birth control pills can help with this. I never used to get this on the pill (before my daughter) but now on Mirena, that pleasant side effect is gone.
One more thing, especially since you also mention eczema in the winter. If you wash and shower too much, you can actually aggravate both the acne and the eczema. Acne has NOTHING to do with hygiene and cleanliness and if you wash off the protective layer of oils your skin produces several times a day, you just send your skin into overproduction.
Mine will let up as soon as it gets warm enough to wear tanktops. I will get some unprotected sunexposure before putting on sunscreen and that really helps (just a few minutes, maybe 5-10).
Good luck.