The ability to change the meter colours is great.
I wonder, if you would also consider including an option to recolour both the Playlist's and 'Piano roll's 'grid colours', from within the same themes settings panel? It would make theme creation more efficient.
Since, many themes settings can look out of place without also matching with appropriate grid colours (which really help sell the overall look of the theme).
Here's hoping! I look forward to the next update...
Thanks!