Bit like MsWolffie, had a few tries & never got the results I wanted & haven't had time to go back to it but I do read all the posts & one thing that comes across a lot is that until you actually finish the piece it is often difficult to see any detail. Having said that from what I can see & what I have read you have no where near enough lines, you only have 149 which from what I have read on other threads is way to few.
Have a read through some of the gallery posts as often people will be asked how they have done it & most of the time an explanation of how the job was done is included.
I have seen some really nice work so know the program works, in my case it's just operator error
You do need a flat surface & some grades of ply the flatness isn't consistent enough, you also need to set your z zero very accurately. Lots of people will surface their material on the machine to ensure it is flat & parallel to the spindle/router.