Carrying: on a regular day, a laptop and a couple books.
If possible, it would be nice to be able to carry a couple bags of groceries, if thats even feasible, i have no idea.

Would I be okay with a rim break? or should I be looking for disc brakes? Was my bad experience a rarity?

What are some indicators of quality bikes? If I go to a bike shop and get presented with a few bikes of the same price range, what are some key features or manufacturing standards I should be looking for?

Will I be able to sell my bike for any substantial amount of money? Or is a used bike hard to sell, and especially hard to sell for a decent price?