Help with estimating bill / understanding new billing tiers

I administer a application review system for a non-profit. The reviewers need to have access to their own views with hidden fields, but also be able to rate applications. To be cost effective, we previously created a new workspace for each reviewer and synced to a table / view in the full applicant database. This allowed us to only need to pay for the 3 administrators and not the reviewers.

Now with the changed plans and billing structure my understanding is that the 3 administrators and the reviewer (the base in this workspace needs to be synced) in each base will be charged $20 per month. This is a HUGE increase in the fee we pay. Is there a more cost effective way to use your system for application review with 7 reviewers (who only have access to one table/view) and 3 admins?