I agree with Andy....
"Often people will go to PS because they are more familiar with how it works - personally I don't use PS unless I really have to nowadays - but, I have spent hours with Aperture since release 1.1"
Like Andy I have moved large chunks of my imaging workflow away from pshop. Like yourself, I too had mixed results using the clone tool (at first). However once you realize the Aperture tools work in a slightly different manner, you will get the feel for how they work fairly quickly. My first forays using Aperture's cloning tool were not very pretty. Retouching, at least when well done, is much like a trip into the wilderness... where the goal is in the end to "leave no trace". After using it for a bit I could match my skill in pshop, and these days I actually prefer to clone out imperfections using Aperture (as long as there is no multi-layer compositing needed).
Try Andy's tips and see if they work for you. One of the nice thing about Aperture, is that the auto levels (you have a choice of two types) actually works better than pshops (even if you custom tune the settings in pshop, auto-levels can create more tonality issues than solve them). I have tried using the recovery tool, but with mixed results. Much like pshops dodge/burn tool the effect can easily just grey down the area.
NIK's selection approach is really a bit novel, and the softness of the selection approach easily leads to a natural effect (where no trace remains of your handiwork). Download the demos, they are free, and fully functioning for 15 days. You can also see some video demos here:
http://www.niksoftware.com/learnmore/usa/entry.php or some really long & detailed webcasts here:
http://www.niksoftware.com/learnmore/usa/entry.php?view=webinars/archive.shtml
I know they are releasing an upgrade to Vizeza in December... but I think they are offering free upgrades for recent purchases (I already trashed the email announcement that came last week, so the details are fuzzy there, sorry).
Also, one of my favorite tools in the suite set in the "Reflector" tool within Color Efex Pro. This tool lets you shine light and illuminate the darkened shadow areas, much as if you were holding a silver or gold reflector on sight while shooting. I noticed your subject was a bit dark in her face (at least judging by the screenshots)... this tool would do wonders on this image. It sounds a bit hokey and filter-riffic... but it really works quite well.
Aperture was wonderful in streamlining and speeding up my workflow. Images that were similar in tone/lighting/composition can be QUICKLY color tweaked by simply copying the adjustments from one image and "stamping" the others with the enhanced settings. Huge time saver there. While NIK did not add speed to my workflow, it added speed when one is taking the time to really finely craft any one image. The speed savings is there (when compared to coming to the same end in pshop), and the techniques are much less arcane and WAY easier to grasp within NIK. I do wish I could "task-build" and do successive tweaks/rotations without leaving the NIK interface... as it is now you need to apply your filter and save out your results, and then go back into NIK again for your next filter. It gets a mite annoying if you are using 5-6 filters, especially so if one is in the same filter suite (like Color Efex).
cheers, michael
PS: these are only screenshots, and your sample was a bit on the low-res side (which had some jpeg artifacting. Some color cast issues still remain, face needs work and sweater is a bit acidy, but without the full-res to start I won't sweat that for now).
ORIGINAL
Click for full size -
Uploaded with plasq's Skitch
REVISED ONE
Click for full size -
Uploaded with plasq's Skitch
REVISED VERSION TWO (darkened down edges, brightened face/center
...much as I used to do in the darkroom back when I was shooting with Matthew Brady)
Click for full size -
Uploaded with plasq's Skitch