I love Redash, but Tableau has a much larger set of features. Redash is pretty good at queries and basic charting. Tableau is pretty good at queries and basic charting, but also offers a bunch of extra visualization types, predictive analysis, native cohort tools, etc, etc.

(That being said, I think a lot of teams are quick to reach for heavyweight tools like Tableau when Redash would be perfectly good for what they need at far less cost)