The reason hardstyle is hard to mix is because the production is in most cases pretty amateur, so they don't follow any kind of set pattern that tracks need to do to be mixed properly. Too many people just make up their own structure which leads to none of them fitting together in sequence.

Hardstyle now needs to be mixed like hardcore, when at first it could be mixed like hard trance or even trance. I guess it comes down to how you prefer mixing - short and choppy (think Mondello) or long and smooth (think Dana). Personally I like long and smooth, so I don't get on too well with bad layouts/sequences.