1. A method comprising: in a multi-vendor cloud orchestration system comprising a cloud computing service tool executed by a processor in the system: receiving, by the processor, a computing environment input comprising criteria that specify a computing environment for implementation; assigning, by the processor, an aggregate score to the computing environment input based on a score range for the criteria; determining, by the processor, characteristics of a set of computing resources offered by cloud resource vendors; determining, by the processor, a subset of the set of computing resources responsive to the aggregate score, the subset including resource members that comprise a cross-platform implementation of the computing environment; validating, by the processor, the subset of computing resources for inter-compatibility; searching a template database comprising configuration templates to determine, by the processor, a selected configuration template for provisioning at least one of the resource members; defining a first user-specified policy rule applicable to performance of the computing environment; provisioning the subset of resource members to implement the cross-platform implementation of the computing environment; monitoring a performance of the computing environment; determining that a maximum number of available licenses have been provisioned under the first user-specified policy rule; notifying a user that the maximum number of available licenses have been provisioned; defining a second user-specified policy rule from the user in response to notifying the user that the maximum number of available licenses have been provisioned; and automatically and dynamically applying the second user-specified policy rule to upgrade at least one resource member of the cross-platform implementation of the computing environment to a new version with a greater number of available licenses than under the first user-specified policy rule.