Zax, I too would want to be using one exclusive tool, to simplify the process. I know filtering varies based on materials plays a big factor and Floyd may not be the best choice in every case. Althou, to be fair seems to be a preferred method among a lot of people work on glass for example.
I think the variable would require a two step at the minimum, with that said. The option to Ditter prior to final product selection being sent to laser for actual engraving.
In my case, I resized and set resolution and saved the new image. Then I dittered based on the materials again saving the image after filtering. The logic on the dittering depends on the material types using Floyd, Jarvis, half tones, etc.
Finally, GRBL generation and actual engraving from the image save in step 2.
The difference here was I was able to Ditter prior to selection for a GRBL generation and generated with grayscale selection and not Ditter which is a change I selected. That is a bigger change in T2Laser doing the dittering I think, but could be wrong.
I would look forward to direct discussions and calabriration with you on some thoughts and ideas.