I'd also at some point pick up the 1/4 impact driver which has like 1,500 in-lb's of torque and can drive large fasteners and bits through pretty much anything. If you already have the charger and battery, it's a cheap add on of about $50-$60 depending on where you get it. I bought a used one off ebay for $25. I already had one, but it was nice to add the 2nd one to my arsenal for $25.
I was helping a buddy repair his deck, and I handed him the 2nd impact driver so we could work faster.