What causes these rough surfaces & strings

[PyramidDave]

I have had this problem for awhile, but would like to find a solution to this problem. This is a part I am designing to go on top of my Delta printer to connect to 2060 v-slot & 3/4" EMT. I have a makerfarm i3v 10" with 1.75mm Hexagon hotend on a wades extruder & using sliC3r 0.9.9. I am printing with at .2mm layer height & 3 perimeters. Infill is.2mm rectilinear & concentric top & bottom. I am nut using support. This seems to only occur with horizontal holes and the one of the 45 degree overhangs. I thought this would be a retraction problem, but changing it from 1mm to 3mm made no difference. Maybe it still is & I did not change it enough. I also changed the travel speed from 140 to 120 with no effect.

Here are the speed settings I am using in that Slic3r:
bridge_speed = 150
external_perimeter_speed = 70%
first_layer_speed = 30%
gap_fill_speed = 50
infill_speed = 60
min_print_speed = 10
perimeter_speed = 50
retract_speed = 30
small_perimeter_speed = 50
solid_infill_speed = 60
support_material_speed = 50
top_solid_infill_speed = 50
travel_speed = 120

Here are the retraction settings.
retract_before_travel = 2
retract_layer_change = 1
retract_length = 3
retract_length_toolchange = 10
retract_lift = 0
retract_restart_extra = 0
retract_restart_extra_toolchange = 0
retract_speed = 30

Let me know if more info is needed to show the problem. Here are some photos of the part. The 1st photo shows the print orientation.IMG_9573_800x600.jpgIMG_9574_800x600.jpgIMG_9575_800x600.jpgIMG_9578a_800x600.jpg