The California Health Benefit Exchange board wants insurers to participate while  allowing some flexibility for  health plans to alter benefit designs. But, at the same time, the exchange needs to keep a lid on the way insurers offer coverage plans. The push and pull between the health plans’ need to earn money and the exchange’s need to ensure a level playing field for all consumers has been a central theme in the planning process, according to a recent report at www.CaliforniaHealthline.com