1. A method, comprising: at a server system comprising one or more processors and memory: initiating delivery of a plurality of message campaigns to a plurality of client devices associated with a plurality of users, wherein a respective message campaign of the plurality of message campaigns includes one or more electronic-messages addressed to at least a subset of the plurality of users; receiving, from the plurality of client devices associated with the plurality of users, campaign-feedback data, wherein the campaign-feedback data is indicative of user interaction via respective client devices with the electronic-messages transmitted to the plurality of client devices as part of the plurality of message campaigns, wherein the user interaction is at least one of: opening, deleting, responding to, forwarding, and blocking the electronic-message; after receiving the campaign-feedback data, generating campaign-tracking data based on the campaign-feedback data, wherein the campaign-tracking data is generated in a form that supports not-predefined newly-generated analytics; conditionally transmitting, when a transmission criterion is satisfied, to one or more remote storage systems for archiving at the one or more remote storage systems, the generated campaign-tracking data; and automatically generating one or more further electronic-messages based on the campaign-tracking data, wherein, a respective remote storage system of the one or more remote storage systems has a plurality of performance levels and the method includes: while using the respective remote storage system at a first performance level, determining that a different performance level for the respective remote storage system is needed; in response to the determination that a different performance level for the respective remote storage system is needed, requesting a change in performance level of the respective remote storage system from the first performance level to a second, different performance level, wherein the performance level of the respective remote storage system includes values for one or more of: an amount of storage space available at the respective remote storage system; a speed of read access to the respective remote storage system; a speed of write access to the respective remote storage system; and shared use of storage servers at the remote storage system.