Using the numbers from my last post, I plugged them into a focus spot calculator and came up with the following outputs.

With a short focus distance we end up with a thinner waist (spot size) at the focus point, but a faster converging beam, so we get a finer spot for etching, but a thicker kerf for cutting.

With a longer focal distance the properties reverse with a thicker spot size and a thinner beam convergence, so better cutting performance and poorer engraving performance.

Keep in mind that I'm not 100% certain on most of these parameters so these are just rough approximations and could be totally wrong.