SpyFu provides insight into the keywords, trending search terms, and associated landing pages from top-ranking competitors in every category. I use this for SEO, but also for new client research, site development, and for development of my own business. It's a fantastic bargain compared to other available tools and an equalizer for smaller agencies. I also like that it provides leading KPI's for website performance long before GA-4 picks them up because it tracks search results to 100 places. This allows me to show results earlier than server-side analytics can track.

The raw data that i get from multiple sources to help make decisions on how to market my customers.

Very easy to use interface that allows you to do some basic searches all the way to very detailed ones.