Did you plot a learning curve? It can at least help find out the possible improvement in performance on the vertical axis when there are changes in another parameter (on the horizontal axis), such as training set size or iteration/time etc.

Changing the world, one post at a time. Sr Data Scientist, Toronto Canada. https://www.linkedin.com/in/susanli/

Changing the world, one post at a time. Sr Data Scientist, Toronto Canada. https://www.linkedin.com/in/susanli/