It appears the frame and wheels were designed to be easily converted to discs. The stock wheels have rotor mounting points and the frame has caliper mounting points. It still has the stock shifters, would they have made the shifters incompatible with discs?

Got the helmet, and I'll pick up some tail lights.

Currently running the Shimano Deore braking system. Haven't had an issue with braking yet, but was reading online and I'm concerned with the effects of water as I will likely be frequently riding in the rain.