I'm not shocked at all about some finding the world empty or the enemies underwhelming. Rage was the same way for me, and so was Mad Max. I didn't mind though, because in those games, the other areas of gameplay made up for it. Plus, this is an apocalypse wasteland, just like MM, I'm not expecting an open world booming with activity and things to do.
That said, in the short time since I've left the opening area I've fought sentries, been challenged to races, found two other Arcs, and fought some giant mutant named Lug or something. There seems to be something interesting everywhere I've been. Finally made my way to Wellspring iirc and have a few more side missions now.
The gunplay is amazing. And I can already tell the powers are going to just make it ridiculous. Starting to feel like a combination of Quantum Break bad ass powers combined with Doom gunplay and over the top gore and that sounds like the best thing ever to me.
Whoever designed the menus though, needs to find a new line of work in video games. Yuck. Plus there are like... too many things to keep track of to upgrade different things. It's confusing as fuck.