OK. The game really has problems with balance. The enemies seem absolutely invincible. I haven't won a single fight in three hours. Well, because instead of a weapon I have a stupid crystal. Hell, even Corruption of Champions is fairer to the player. In addition, I am not very happy about the inability to interrupt rape.
The game does have issues with balance, but if you're playing on one of the easier difficulties, it sounds like you are approaching the fights wrong.
The crystal in not worse than any other basic weapon, it is enough to beat some of the weaker enemies, if you know what you are doing. Spam the Crystal Strike to get the crit on third use, maybe block if their damage is low enough to mostly negate and you can still get your own damage through.
If you go out during an arcane storm, like the one that is active just as the game starts, you can easily beat most enemies you will meet on the streets of Dominion by just teasing them. The experience and money you get from looting them of everything they own you can use to further improve your chances.
And with level drain, you can also sex the defeated enemies for extra experience. As far as I know, you only need to have the perk active and then do quick sex, and it works even if they are the ones defeating you.
In general, I find that focussing on teasing damage is the easiest. Any non-demon enemy is capped at 100 and even demons take double health damage for any tease damage, once the bar fills up.