I like to keep the center chord length about the same for my quiver of kites. To make the kite bigger or smaller, adjust the aspect ratio. For small kites, I go a larger aspect ratio. For large kites, a high aspect ratio. If you try to keep the aspect ratio fixed for a quiver of kites, you will find that the bigger kites are "slow".
For light winds, you may want to explore fixed riding with a pulley bar or fricken loop (rooster ring). Awesome setup for unhooked riding. Depower is overrated for light winds.