Tim_Iowa

As fietsbob said, do you value vanity over safety? Do you ride with or without a helmet? Personal choices, but possibly grave impacts.

Wheel and pedal reflectors are extremely effective because they move in a way that instantly identifies you as a bicyclist. They flash and twirl, and that catches the eye.

The flat front and rear reflectors are less effective because they are a single, un-moving, dim point of light. Actual head and tail-lights are more effective than the reflectors, but they aren't very visible from the side.

If you never ride after dark, or never cross paths with cars (remember that many bike paths intersect with streets), then it doesn't seem unsafe to remove all reflectors. You get a cleaner look and save a half an ounce.

Otherwise, it's smart to keep the at least the wheel reflectors on (and the pedal reflectors if yours have them), or replace them with something that works with your aesthetic. Drivers are increasingly distracted, so it's good to be a bright shiny thing.

I recently picked up a blacked out Foundry Auger. I added some of the spoke clip reflectors that ShortLegCyclist showed, and some small patches of 3M reflective tape in other places like the pedals and fenders.