I find the SqlLab in apache superset to be very good, and I have duckdb as a data source (anything that supports SqlAlchemy works). It works very well. To be honest, when I first saw the screenshot, I thought it was SqlLab. I haven't actually tried the duckdb ui, though.
That is really interesting. I am thinking of toying with same combination for my small project. Can you share a bit on your use case? Would love to know more.