This is becoming a little tiresome, I am on a quest in a mine and suddenly the enemies are 50+ with stealth being totally rubbish, balance is appalling.
Looks like the latest Wolfenstien will have to satisfy my gaming needs.
The fundamental problem with that aspect of balance is one of the fundamental problems with FO76 being multiplayer. It's simply not suited to being MP.
What's happening is that mobs are being spawned scaled (to some extent) to the level of the nearest player when they spawned. So when another player enters the area the mobs can be wildly out of scale. In some ways it's less of an issue than it was before because changes have been made to make the game easier for lower level players. In other ways it's more of an issue than it was before because a higher proportion of players are higher levels.
One viable solution is to play the game as an exploration game rather than as a quest-following game. In that respect FO76 is sort of balanced because Fallout games have always been largely about exploration and that's how most players want it. If you remain in the Forest zone, you will never have the problems you're having because mobs in that zone do not scale. If you explore the forest zone, doing the local quests in that zone if you like, you will be able to be powerful enough to handle almost all mobs. A L30 player with good kit can easily handle most L50+ mobs unless they get swarmed.
I left the forest zone at L25, but I was in a full suit of power armour (T-45 initially, Excavator after doing the quest) and I had a rifle and a shotgun and some good perks for that build. I wasn't even looking at the level of mobs because it didn't matter. Only some specific types of mob were a problem.
What equipment do you have? IIRC, you're in the high 20s for level. Do you have the highest level weapons and armour for your level? What weapons and what armour and how have you modified your weapons and armour? If, for example, you're wearing unmodified L5 leather armour and have an unmodified L5 melee weapon, you're in for a very bad time of it anywhere outside the newbie areas in the forest zone.
What perks do you have in play while out and about and at what level do you have the perks? That can make a lot of difference. Some obvious, e.g. the right perks can increase the damage per shot from a weapon by 60%. Some not so obvious, e.g. the right perks coupled with a shotgun can enable you to quite reliably stunlock most mobs and thus serves extremely well as a defensive measure.
Nukes Dragons has an excellent build planner for FO76. If you want to plan out your perks, that's probably the best thing to use. Although it doesn't work with Pale Moon for some reason.
Something I didn't notice for ages, so maybe some other players haven't noticed it either - the protection given by your armour depends on its condition. So it pays to keep your armour repaired, preferably swapping in the Fix It Good perk card when repairing to increase the condition to >100%.
Stimpaks hotkey to h by default, by the way. When you need a stimpak, the last thing you want to be doing is opening your inventory, selecting the aid tab and scrolling to get to stimpaks.
VATS is extremely useful in FO76, much more than some people expect. It's basically an aimbot and an enemy locator.