I've done something similar for several prints using the "infill extrusion width" and "print sparse infill every ___ layers" settings. What it accomplishes is that the infill is printed with the normal width/height that you started with, but the top solid layers and your perimeters are printed with a much finer resolution, which makes the outside of your part look much better.
So, here's an example. Let's say you are currently printing with 0.2mm layer heights and 0.5mm extrusion width. However, you want to print the outside of your part with a finer resolution - say 0.1mm layer height and 0.35mm extrusion width. If we made that change for the entire print, it would go a lot slower since you are also printing your infill at this same fine quality (which usually isn't necessary). Our goal is to use this high quality setting only for the outside of our part where it matters most.
So to do this, go to the Layer tab and set the "primary layer height" to 0.1mm. Then go to your Extruders tab, click on each extruder in the right-side list to load its settings, and change each one of those to have a manual extrusion width of 0.35mm. So at this point, our entire print would be using these finer quality settings. However, if you go to the Infill tab, you can change the option to "print sparse infill every 2 layers". This means that the infill will be printed every second layer and it will be twice as thick. So you will print two 0.1mm outlines for each one 0.2mm thick infill layer. It saves a lot of time. You can also change the "Infill extrusion width" to 150%, which will help make sure your infill is closer to the original 0.5mm extrusion width that you started with.
I've used this several times and it works really well. Produces very fast prints by only using high quality settings for the exterior of the part.
I still believe it would be useful to have a top layer specific setting such as Slic3r has. One trick I can to play with slic3r is to significantly overextrude the top layer (like 125%). If you have your infill settings right, and enough but not too many support layers underneath, it is possible to squish the plastic down into the preceding layers to produce a very smooth top layer where you can hardly see the extrusion lines at all. It isn't as shiny as the layer against the glass bed, but it can be much more aesthetic than the default top layer. However, if you over-extrude this much on the rest of the print ... it won't work. This is one feature I do miss from slic3r, though in general S3D is much nicer to use.
I do agree that S3C is nicer to use I'll sure miss some features (auto rotate models based on selected face, the obvious super high speed, the slick UI) but I rather have the models printed properly. Fist and foremost thats why we got a printer, right ?
I will be giving this software another try in 1-2 years (maybe)... Back to Slic3r now.
IMO, S3D should have all the features that free software has, so I am saying yes to this as well.
Many people are asking why pay for S3D when it is updated so infrequently (and the check for updates feature does not actually work) and the free software has features the expensive software does not have.