What tools do you like? I'm a programmer, so things like D3 and matplotlib are great too.
Chord Pro (https://datacrayon.com/shop/product/chord-pro/),
Plotly (https://plotly.com),
Plotly Dash (https://plotly.com/dash/)
a) OpenRefine (formerly Google Refine) for cleaning and filtering - i.e. exploring and making sense of new data dumps
b) Grafana for dashboards, once the data structures are defined.
c) looking forward to this Pinterest-backed data explorer https://www.querybook.org/