So I'm in the kick the tire stage.  My Yahoo group has about 1700 folks,
and I suspect that the free version is probably adequate.  One obstacle is
getting all those members over to the new site without going the invite
option.  I understand your premium version permits that, eg direct
insertion of membership.  For us, that is a one time event/need.  So to
induce groups to move over to yours without having to go through the invite
hassle, why not offer a one time fee OR free window time period, to transfer their membership?

I suspect many groups with minimal needs, would find the offer very
attractive as an easy way to migrate their group.

Separately, i tried to post this here via email, and it came back as undeliverable.

Just a suggestion.

butterandpeanuts,

I understand your premium version permits that, eg direct insertion of
membership. For us, that is a one time event/need. So to induce groups
to move over to yours without having to go through the invite hassle,
why not offer a one time fee OR free window time period, to transfer
their membership?

Done and did. See:
https://groups.io/org/groupsio/beta/thread/pricing_changes/1595

I had the same question and Mark provided a solution. A "group transfer" plan: one-time $10 fee.

-- Shal