OpenStreetMap.org tile rendering operates on edge of its capacity. It's possible to get more from already existing cluster if rendering queue is not continuously dropped, but instead is preserved and processed during low load hours.
Ttile.OpenStreetMap.org uses mod_tile and renderd to manage rendering queue. mod_tile is currently a core ecosystem project lacking an active maintainer for years. There are currently 19 Pull Requests that nobody merges.
I tweaked values in source code to allow for a longer queue. Pull request is available at https://github.com/openstreetmap/mod_tile/pull/152. In comments there was a proposal to make it a configurable parameter.
I offer 50 USD to person who manages to:
create pull request to mod_tile/renderd that makes queue depth a configurable parameter, and set defaults to preserve the queue to shift day's load to night;
get it depolyed to tile.openstreetmap.org adjusted accordingly.
Shift should be visible on https://munin.openstreetmap.org/openstreetmap/render.openstreetmap/renderd_queue.html graphs, most likely by Dirty queue growing beyond 1000 tiles per server, and being non-empty for the whole day, shortening during the nighttime.
This should make the map browsing experience better for everyone.