We get a lot of performance issues from suggested facets - on large tables we end up running multiple SQL queries for every column (one for column facets, one for date facets, one for JSON facets), each with a 50ms facet_suggest_time_limit_ms time limit but even with that in place these can add up - 20 columns could be 20 * 3 * 50 = 3000ms, not including overhead of the Python code that manages the queries.

Since these are really just suggestions, an optimization could be to only consider the first 1,000 rows in the table. This would be enough to spot likely date / JSON / column facets and should be much faster.