you get experience for the skill three and new "amulets" to upgrade both weapons and armors by killing new and strong beasts.
and the challenges gave you the strongest weapons in the vanilla game and dlc if you get all gold results.
Agreed, game mechanics-wise, those are helpful, and the beast areas are great for the tutorial challenges (which give a LOT of XP and encourage you to try out the weapons' abilities), but they just felt like filler and not good filler (it's not like the beast areas are well-designed encounters, they're just beasts lumped together unlike the Cauldrons).
I probably should have clarified, since I care more about the story/narrative, stuff, but even things like the Vantage story didn't really shed light on the main story like I'd hoped. Also, collecting coffee mugs was a minor plus in that the activity felt "funny" (ha ha if only Aloy knew what they really were ha ha - meh in terms of a joke), but it also felt lame in how forced it seemed - all the "collection" merchants are basically waiting in the center of Meridian to complete the activities, which make them feel even more forced. But yeah, you can get good game mechanic bonuses for doing them, but that didn't validate the gameiness of their presence.
I felt the DLC was better, but it still had some of the filler elements (which you can't avoid). The "DAEMON trees" for example, did feel tie to the story even though they were technically filler content.
