Luring healthy risks to a high cost product

[tope]

I m looking at a scenario where you have 2 products, a PPO type product and an HDHP...The HDHP attracts younger healthier members due to low cost and saving component, but now you want to attract these younger members to a more costly PPO, but you dont want to change the price as much, is there any other incentive to get healthy risks to join a product like PPO, bearing in mind that cost is one of the attractive pieces of the HDHP in the first place