I think you can get mods to make it harder by spawning more 1 & 2 star enemy or other perks to them, but playing legit all you can do is limit yourself, eg one guy plays without a bow, others use the light armors, no shields, whatever 'crutches' you find make it easier, take those from yourself.

If its too hard, you have missed some upgrades to your gear somewhere. Once you have the best stuff in your current zone upgraded to tier 3 or 4, and decent food, nothing should be terribly dangerous** there anymore including even the boss or the zone's epic enemy (troll, abomination, golem, lox & zerkers)

** one on one, that is. Leeroy thru the zone and get 20 guys on you is still going to end badly if not careful.