At least some of the complaints (cave-ins, monster dps) sounds like you aren't sinking enough points into vitality. When I was first starting out, I tried putting most of my points into strength/dex (to equip better items w/o using potions) or int/spirit (to have unlimited mana). And got hammered. The game has pretty good balance, in that some strategy has to be used for the unglamorous skills like vitality, armor, and resistance.
Cave-ins and monster swarms pissed me off at first
, but I'm getting better at the old saying: "He who lives and runs away, lives to fight another day."
(Closely followed by the Daffy Duck saying: "I may be a coward, but I'm a greedy coward." )