it would be cool to support a "messageGroupId" prop in queues, so messages can be grouped by tenants.

Its to avoid "noisy neighbor"; its not very clear how queues process messages if tenant A sends 1000 messages and another B sends 1; will we have to wait to deal with A 1000 messages before processing B message ?

If grouped by tenant id (or whatever the dev needs), it would be more clear; and better for SaaS purpose.