I started on Normal, hardcoe off.
At about level 5 I decided I was getting killed a lot more than I wanted (I'm primarily a casual player), and also going through too many stimpaks, so I dropped the difficulty down to Easy.
This didn't seem to have much affect, so at about level 8 I dropped the difficulty down to "Very Easy". But I'm still getting slaughtered.
I'm at level 12 now, and one swipe from a Fire Gecko nearly kills me, and Powder Gangers, etc. do the same thing - they get my HP down under 50 before I can get two shots off. I spend the rest of the battle injecting stimpaks, drinking sarsparilla, turbo, jet, etc just to survvive each battle.
I have to pump about 60 rounds from a Cowboy Repeater (in pristine condition) into a deathclaw to kill it.
I'm not a great player, but I'm not this bad. Lots of experience with FO3, ME1/2, All Halos, etc.
And what's with the repair costs? 3500 caps to repair a Fire Axe or Shishkabob?