I sweat like no other, even in single digit temps when I'm snowboarding. I wear a polyester long sleeve cold gear shirt for my base, then a heavy non-cotton hoodie for my outer layer. Doesn't sound like much, but I've found that it keeps me dry and I stay warm enough and comfortable. It it's not warm enough, my mid layer is a really thin, high quality fleece quarter zip underneath that. Need good fleece and keep it thin, otherwise if you're a heavy sweater like you say you'll overheat quickly.
On days where there's exceptional precipitation or high winds, I just have a cheap non-insulated 10k, 10k jacket that I put over top of either my base layer alone or base layer + THIN fleece.
These give me enough different combinations to adjust to depending on conditions. Although, I will say that when I do break out the actual jacket (I try not to) that the inside of it still can get wet. But as long as I have that fleece on it usually keeps me from getting soaked myself.