On #Mastodon, for larger instances such as https://mastodon.social, you should use the #Explore Tab to discover new users and posts, since the local and federated timelines will be choked.
For smaller instances, it might be harder to maintain the Explore tab, however, the Local and Federated Timelines should be much easier to handle.
For personal instances, why do we need a local timeline? The Federated Timeline should be easy to handle, though.