I think it's very important to continuously think about pushing through your heel on many moves, to make sure they target the glutes more.
I've also found that the 1-legged lunges/squats (with back foot up on the high step) can easily shift into the quads more than the glutes if I use too heavy a weight, or if I don't allow enough recovery (YMMV). I find that by puttng a short break (a minute or two) extra before this section, and between sets, helps me keep the emphasis in the glutes. Also, again thinking of pushing through the heel of the front foot, and almost thinking about being able to lift the back foot off the step.
As for soreness, it's not a necessary sign of progress. Some people tend to get more DOMS than others, and there are many things that can reduce it (stretching, eating an alkaline diet, refueling after a workout). You may also be someone who flushes lactic acid quickly (I recently saw a show about Lance Armstrong, and they talked about how his muscles recover faster than most people's and how his ability to flush lactic acid accumulation is much better than most people. COuld be from training or genetics, or a bit of both.)