Fitbit removed everyone’s badges during the move to Google Health. I think it would be cool if StepSmash had badges for the number of steps I’ve ever taken, or the number of stairs I’ve climbed, and other interesting milestones just like Fitbit had!
also related to this, maybe some stats for your profile, something like “longest distance/ biggest number of steps over 24h” to have something to challenge you to push yourself further
Yes! Were you ever a Fitbit user? If not, this is exactly the kind of thing Fitbit did a really good job at with their badge system. They had a ladder of badges for steps, floors, and distance. Eventually you earn as many as you’re going to get in your daily life.
But, at least in my experience, I’d go on random vacations where I’d be walking 4x more than normal questioning life choices that lead me there, and then suddenly I’d get a little push notification from Fitbit congratulating me on a new daily steps badge to make it feel more worth it 
The full list of what Fitbit offered is here Ultimate Fitbit Badge List: 62 Distance, Floor, and Lifetime Badges | Develop Good Habits
I used Samsung health, they didn’t go that far, I think the last one is at 40k steps, which is kinda underwhelming, since it makes you feel like any steps above that redundant.
also what Samsung does really well is the starts overall, per week /month/ year. they got some nice graphs for that, maybe something to keep in mind for the future 