The G1000 system displays wind vectors which helps you know what to expect, but I think the pilot still has to decide on crab angle and timing. Of course they can look at the magenta ground track vector on the HSI to tell them if the crab is working, and how much to add or subtract, so it is greatly simplified. Part of the traditional art of doing holds involved using various methods to know what the upper winds were doing. There are a number of rules of thumb to use for each wind situation, a bit too much to list here. I recall having the same trouble as the OP when I was an instrument student, my instructor either did not know any tricks or he was too lazy to teach them to me. As a consequence I hated holds and wanted to think of them as a either a waste of time or a hopelessly sloppy maneuver, when the problem was I had never been taught how to do them properly. I have far more respect for hold techniques now than I ever did as an instrument student. They are challenging to do well and I have seen very advanced pilots get their panties in a wad in practice holds.