A little bit of info regarding time management and why do I do sculpting the way I do it.
Unfortunately having both written and practice briefs and other additional personal studies going on time management is absolutely critical when it comes down to sculpting.
I've learned that it's better to block in shapes and stretch and tweak them when on lower subdivision levels and then detail the existing geometry after a quick polish at a high resolution level.
One of my biggest mistakes was that I was rushing and subdividing to higher levels and trying to add detail when the general shape wasn't at it`s best, lacking silouette expression, and thus it looks just as bad with or without details.
Another thing I've learned was that it's too time demanding to try and polish everything to a mechanical level when the actual size of the rollerblade is quite small when character is all visible.
Balancing how much detail and polish I add to an element and how big is that element with regards to the whole picture can change the time in which I finish the model. Adding too much detail to an area that will never be seen closely enough is useless and burns up energy and time.
Another aspect worth mentioning is the triangle count that can be held within a 1k/2k/4k normal map. There's really no point in adding 10 million triangles on a boot that will be uvmapped to 20% of a 1024x1024 normal map as barely 1kk triangles will shine through and remain crisp.
So in conclusion one very important lesson I've discovered the hard way through my mistakes, is to work low poly and get silhouette shape first, once happy subdivide and polish fast. After the whole model is polished to a satisfactory level, think about how big is that particular object, how much space will it take on the UV map and then go on to continue with detail on it or not.