Combine segments for running, hiking, and walking.
I realized there is a separate set of segments for hiking, often on the same hiking trails that are popular among runners. It doesn't make much sense to me. I'd say the line is very blurry between trail running and hiking - both use the same form of bipedal movement and segment times are not that different, at least for uphill segments. And there is basically no difference between hiking and walking, at least no more difference than between running and trail running. All of these activities should share the same set of segments.
And once you decouple segments from the activity type perhaps it would be easier to introduce trail running as a separate activity type.