An online tool gave me these performance results, will you implement the recommendations on the theme?
We design and develop themes with conversion and performance optimisation at the forefront of everything we do.
Usually the best improvements come from you optimising any images you upload. See these articles: https://www.flairconsultancy.com/blog/2017/07/optimising-images/ and https://developers.google.com/web/fundamentals/performance/optimizing-content-efficiency/image-optimization
It’s also worth checking whether any apps or widgets that have been added to the site are affecting the speed and, if your theme has been modified, whether the score is the same on the base (unmodified) theme.
If you’re experiencing significant speed issues, check https://status.bigcommerce.com/ to see whether there are any platform issues.