I didn't think to try expert mode, but recently had to troubleshoot a query issue at work where they wanted a query to run every 1/10 of a second on a largeish dataset. Unfortunately, the query was taking about 1.1s to run, so just a little outside the 0.1s desired window. I was able to use explain query plan to figure out to add an index to each of two tables that got the query from 1.1s to 0.0001s. I should go back now and see what expert mode suggested.