Your community probably has star members. These are people with the most knowledge, most authority, most experience. These aren’t just the high contributors, they’re the experts.
You should be promoting them. You should promote them inside and outside the community.
Get them interviews in relevant trade magazines, get them guest-post slots on top blogs, pitch them to speak on behalf of the community at events. Act as their PR agents. Good publicity for them is great publicity for you. It gives fellow members something to aspire towards.