Oh, I've only just noticed this discussion.
Mind if I butt in? No? Thanks!
1) Servicing your own skis is a Good Thing for many reasons. You get to select your waxes, edge angles etc etc.
2) Race skis are generally not great as all-mountain skis, just like a race car is not great as a family car.
SL and GS skis are set up for exactly that, in terms of their edge angles, flexibility, length and turn radius. They are not really wide enough for off-piste by today's standard, and the edges then become irrelevant: you don't set edges in powder. Also, GS skis are a bloody handful on moguls.
3) Regarding edge angles. Side edges generally default to 89 on general purpose skis, which combined with a base edge angle of 1 degree gives a 90 degree angle on the metal, and is reasonable. If you are skiing icy conditions, then sharpening up to 88 or 87 is fine, and will give a keener line in ice, but they will become dull more quickly, and you will need to hone them more regularly. Base edge angles in general should be left alone. You can only increase it from the default 1 degree, it's not possible to reduce it unless you stone-grind the entire base down which is beyond any home fettling. The base edge angle defines how much you need to roll onto the edge before it begins to set. If you want the edge to set early like in an SL ski, you may wish to have it set to 0.5 for example. That will start turning quicker, but will make it twitchy and unstable at high speed in a straight line, as the edges will catch all the time. For a faster line downhill, a lazier angle will make the ski more stable and less twitchy at the expense of a slower response to a turn , as you need to roll it more to set the edge.
4) Waxes: I used Holmenkol when we were racing, but for general family use I tend to go with cheapish universal like Data unless I'm going somewhere bloody cold. Cold snow wax ( like drymat wax ) is bloody hard, and damn near impossible to scrape.
<ETA> 5) Wax solvents: Did you ask what these were for a few posts back? They are not used for routine waxing. They are used to remove all traces of wax prior to a PTEX base repair, with a hot PTEX repair gun. Traces of wax causes the repair not to 'take' properly to the original PTEX, and it will strip out quickly.
I've never used masking tape. Don't use so much wax that it's pouring over the edges. A wee dribble is fine, and can be knocked off once it's hardened.
The Perspex scraper will usually have a wee notch out of one corner, this is to scrape residual wax off of the edges.
Don't worry too much about getting the brushing 100%, you never will.
You will find that it will take one or two runs for the snow to finish that job off.
That's why we do practice runs on practice skis, but still take the race skis for one or two runs before the race; they do speed up.