I agree with having tiers as an internal rather than an external matter.
Externally-facing ranks create pressure to escalate customers through levels just to keep them engaged. Which is fine if you are creating a kind of competitive community, but I prefer a more collaborative and celebratory one. Internally, tiers work better as a routing signal: "this account is CAB-ready, this one is G2-ready, this one is speaker-ready, etc, each with its own bar, rather than one ladder everyone climbs.
If external recognition still matters to advocates, a named badge or public thank-you tied to a specific contribution should be enough.