We are providing a SaaS Service (currently in open beta) and thinking about our pricing tiers. We want to offer plans that grow at the same pace that our customers businesses grow.
We are thus thinking about using "user limitations". The simple idea behind this thoughts is "The more users they have, the more money they make, the more resources they use and the more we have to charge".
Based on our statistics and surveys, the pricing tiers will suit most of our future customers. We have however a few customers that will not fit.
These customers have thousands of end-users that are using our services but they do not make any income or far less than our services would cost them.
I'm looking for ideas on howto handle these customers. They like our services but will no longer be able to use them because they will reach the user limitations and cannot afford to switch to a bigger paid plan.