there really needs to more of a tell for cursed items, or at the very least less of them. my reward for clearing a dungeon was that my best character can no longer do anything until they take 200 damage
Currently cursed items are heavily skewed towards common-very_common rarity, so you'll encounter more than expected of them in earlier dungeons. It's something that'll get better with time.
You can tell when items are cursed though, since the rarity will not correspond to the dungeon level. You'll never find very_rare of legendary items in novice dungeons, and even rare items should be suspect.
Basically, assume any item may be cursed when you try to equip it, especially good gear from lower level dungeons. Some cursed items can be fairly good or situationally useful once uncursed though.... so it's worth collecting and using even cursed equipment.
You'll be forced to switch "good characters" around a lot though, as they get ruined by curses until you can free them. I just lost my best Paladin last night, and it'll take maybe ~10-20 runs to free them. (Cursed to another class - was using PLD and a damage char to carry two useless characters through an easier dungeon to uncurse them.... Got stuck in a longer fight, PLD armor durability went to 0 - and it was game over for her. She was cursed and ruined before I could finish the fight. )