How do you make dashboards load faster? what is the quickest way to do it?
Along with Summary indexing the other alternative option is making a search has made available for later use by creating the savedsearch.
For 95% of cases, the biggest thing will be to use summary indexing:
You can also look at things like caching dashboards, referencing existing search jobs, and etc., but it's likely that everything you want will be solved by summary indexing.