The problem seems that Ulbuka is supposed to be ridiculously hill-y, forcibly so in Kamihr Drifts' case (which is really lacking places to use climbing), but it's not handled so well. Take an old zone like Beadeaux for example, it leads you through a series of tunnels, and has hills/walls all around you throughout most of the journey, but eventually you get to climb on top of the hills and finally get to feel less claustrophobic. I think it's better to look at the new areas as dungeons, even the outdoor areas, as they're supposed to be hazardous and horrible to adventure upon. They simply have little variety apart from completely changing areas.

This is one of the reasons I like Yorcia, it's a lot more spacious then it lets on and you actually have breathing room in reives. There's enough stuff littering the ground around you that makes it feel like a jungle and keeps it interesting.