I'm guessing you missed a significant amount of content. I spent well over 100 hours on a single playthrough.
No idea, could be, but I also started using elex potions basically from the beginning of the game so I could use the sword I accidentally found in the toxic basement of the building where a zerker and his mutant brother hid. After that it was basically lawn-mowing everything in a very quick fashion, and it got even easier when i got a plasma gun and joined the Clerics for that damage boost.
What I forgot to mention earlier - it's kinda nice that PB always tries to create believable environments. What I mean, every citizen has his own timetable, they move around, do stuff, there's a food production chain in every major city, change of guards and so on. There are some anachronisms (like working radios), but it might be a cleric propaganda tool or a joke.