The steps to improve your skill between 90 and 100 are pretty steep, but the rewards is often not very high.
I would like to see better rewards then a bit of extra luck or 0.0005% change on making a better weapon, like the reward to auto-craft items in that area (when you have been doing it so long that you have earned the title 'grandmaster', you should be able to craft such an item in your sleep, right). Or crafting 2-5 items using the same rough materials (you should have better feel and experieance on how to get the most items out of the base material at level 100%)