I have ended up with a voronoi style design that I am printing flat in multiple pieces. Its 2mm thick and I have perimeters set for 1mm all round so it's solid.
Here are some (very) close ups of the issue. The finish is like a washboard basically but it doesn't look too terrible without the zoom.
I am not sure what it should really look like / how smooth it should be but I figure it should be a bit better than this.
It seems to be worse X -> Y as pictured but still happens in the other direction.
I was overextruding prior to printing these so I calibrated e-steps by trimming the filament square with the end of the Bowden and extruding 100mm into the air and measuring. (ended up at 93.7)
I then figured It may be extrusion width so I did a test cube and was at about .63. Changed to .87 extrusion multiplier and came out to .55 pretty consistent around the cube (although was about .2 off on the 20x20 dimensions)
Not sure the best place to start on this. I have tried reducing flow on the printer while it is printing, slowing down 80 -> 50%, temps from 215-230, bed temps 80-90. I have a nice little bag full of pink plastic at this point

Thanks for any help!