To gradually increase the number of slots for validators, I propose scheduling the increase over time.
The scheduled event mechanism (submitted by external motion to council and then pass to referenda queue for vote) aims to increase the number of validator slots steadily upon certain conditions. In the case of Polkadot:
This mechanism can be canceled or completed after 100 eras, and in that moment the community can review network metrics. The proposal aims to avoid an abrupt increase in the number of validators on the network.
What is left to decide is if we could request the Technical Committee to fast-track the proposal, in order to avoid a long waiting period until execution. Open to hear your thoughts on this.