Yeah multiple runs is def the kind of game it is. My first was a Durge and I thought I really explored most of the nooks and crannies. My friends are behind me still on their first one and regularly ask me about stuff I had no idea I missed once or twice! Started run 2 as a good character and it's like a whole new game.
I loved it and immediately went for plat after I finished the first time. The combat was a little rough at times but not really all that challenging. Way better than the movies by far. The characters, story, and acting were all phenomenal
I finished my first run the other day and had no inventory issues. I did stop picking up every single thing not bolted down about halfway through the game and still ended with a surplus of 25k gold. You can select multiple items and send to camp/stronger party member or add to wares for quick sell. I was a low STR sorceror so just sorted by weight and sent it all over to lae'zel whenever I was carrying too much. Didn't really go out of my way to go to merchants