Hey again!
If this dashboard is the same one as from this question: http://community.retool.com/t/result-exceeded-maximum-size-556-308mb-500mb/4553, then I think you may be loading in a pretty significant amount of data. Seeing the dashboard slow down as you increase the amount of data is somewhat expected, and the slower of an internet connection your users have the longer it will take to load.
Is it possible to return the results that you are looking for from your SQL queries, instead of the entire raw data? For example:
SELECT COUNT(id) FROM USERS
Instead of:

SELECT * FROM USERS
And then referencing {{query1.data.id.length}} inside of your UI to calculate the count using javascript. Both options end up with a single count returned, but the second option involves downloading the entire db table into your browser and evaluating it with JS.