I have a feature request for step goals. My goal is to reach 10 000 steps each day. If I reach that by having 5 000 steps one thay and 15 000 steps the other day is just as good as reaching 10 000 every day. My suggestion is that the todays goal should be what you need to keep the running average of the last 7 days above your own step goal. So if the last 6 days is 58 000 steps, tomorrows step goal will be 12 000 steps.
This would make it more fun and inspiring trying to keep up the number of steps without losing the streaks ( and badges ) on random days below the goal.