In certain settings you have the ability to control the lights for your presentation. Will you need more lights on the stage from which you are presenting or more lights towards the audience? A good light plan could benefit the quality of your presentation.
When you have a bright spotlight pointing at you, you will experience that it is more difficult for you to see the audience. Do you need to see the audience? Think about the balance between the lights pointing at you and the brightness of the lights towards your audience. Also think about the ambiance that you want to accomplish. Intimate with low level of light or a very bright room. Front light, top light and backlight for your. No bright lights towards presentation screen to avoid difficulties of your audience to see what is on screen (wash out effect). A well though off, good designed light plan will support the quality of your presentation.