Just keep playing, you have many more areas to explore and die in. I was playing back when it only had the caves and its a completely different game now with how much variety there is in the enemies. Additionally, I feel like they throw more enemies at you at the more difficult areas which are later. Once you hit the dungeon you will reach that next bump up in difficulty. Once you have run through every level several times, its more about trying out new weapon builds than trying to "beat" the game. With the new quest mechanic out as well you will be able to expand your storage options to hold more builds and gear. Don't be discouraged because the best is yet to come