If its 2012 (which my cls is) then I would clay it with a clay mit to remove all the contamination that will be there after 10 years , then either hand polish or better still machine polish. It will make a huge differens even on a silver car. (mines black which really shows the difference for at least half an hour till it rains then it does what black cars do)
I've found that if you use a metal remover such as Iron-X or similar, something to remove Tar and a good clean with a car shampoo designed to strip off any wax, then you may only need to polish marks/scuffs, especially on a lighter coloured car. If you use clay it will tend to marr the paintwork to some degree, more noticeable if it's a darker colour and then you'll need to polish out the marring.
You can just go over the marring with a filling type wax though and save the whole buffing process. Sure it'll wash out eventually, but it does save a lot of effort and unless you are especially careful when washing you will gradually end up with minor marks and marring over time. Just depends on how much you want do spend buffing in time and/or money really.
When we got our C200 earlier this year I decontaminated the whole bodywork and wheels, then machine polished it in stages over a period of about a week. To be honest looking back at the photos it's hard to tell which bits had been machine polished as it's lighter colour (Diamond Silver, which is a very light metallic blue).
The whole nearside had been machine polished in this photo, but the bonnet just had some spray on detailer in this photo:
After I'd machine polished the bonnet, it felt smooth already due to the decontamination, perhaps looks a little shinier but may well just be the lighting or the camera was in better focus. It's nice that I know the whole car has been gone over now and I have rectified a few small marks that polished out/wet sanded a couple of deeper marks as best I could. I think going forward though I'll just decontaminate it and whack a coat of some kind of ceramic type spray to keep it looking tidy:
Probably dropped 10cc of something on the lip
I see what you did there.