Optimizing file size for shorter cut times?

[myxpykalix]

I made a file in millwizard of a boxlid that was 46.5"x21.5" the roughing pass with 1/2" endmill was 676k and the finishing pass was with a 1/4" ballnose and was 6.6 megs and probably over 200 thousand lines(?)and it took around 15 hours to cut the finishing pass at 5 ips. Is there a way to optimize your file size to help it cut in a shorter time?
Increasing the ips speed is not an option as it doesn't have time to reach its speed due to the carving patterns in the file. It is similar to the chairback i did a whileback that is very ornate.

[knight_toolworks]

I think it is the size of your piece really. 200k lines is not super terrible on a lithophane. as you discovered it is the depth changes that slow things down quite a bit.