1)You don't have to have the handlebars very low.

2) For commuting I suggest getting secondary "interrupter" brake levers on the upper portion of the handle bars. These function like the dual handle brake levers of the 70s 10-speed boom, except they are connected by the brake cable, and not a rigid mechanical link. This will let you have quick access to braking when you are riding the uppers which gives you a slightly more upright position which can help with visibility in slow, busiy traffic situations.

3) Consider a glasses-mount or helmet mount mirror. This will let you visually sweep through your rear surroundings with just minor head movement, which helps when you are leaning forward while gripping the brake hoods, or even lower on the drops.

4) I rarely ride in the drops anymore, just when pushing agains a stiff wind.