Your ideas for Sablono

For pro users it could help to indicate with a colour if activities where finished on time or not instead of making all finished ones green.

The colour scheme could even be customise-able including the thresholds when which colours are supposed to be shown.

To be able to review this in a meaningful way on the Activity Tracker, zooming out to really make it a heatmap then zooming into the areas that seem relevant would also be helpful.