Might I ask what setting(s) you changed/tweaked here? I've looked all over in the GECK and can't seem to find this.
Here you go: ?fWeapSkillReqPenalty
The one for strength requirements is ?fWeapStrengthReqPenalty, but this seems to be broken or was never implemented in the game
I'm almost exclussively a guns user and I think they're pretty balanced. First time I got my hands on an Anti-Materiel rifle my jaw dropped when I saw how much damage it did (I had level 100 guns mind you) and I thought "this is overpowered!" but then I realized that it has some major drawbacks: it weighs 20 lbs and and 40 rounds for it weigh 10 lbs (and I usually carry around about 100 sniper rounds between the different ammo types 50 normal rounds and 50 special rounds) Cost wasn't really an issue since you can swim in caps if you literally play your cards right XD Of course on normal this isn't really an issue but I don't play on normal. Given your carry weight edits this can make carrying one and the ammo for it a bit of an issue if you want to have space to haul the loot you want to sell as well. So it's balanced IMO.
I'm going to decrease both the DAM and the 100 Guns skill requirement. The Dam, because, with my mod, if you have 100 Guns skill you have a 2X Dam multiplier. and the skill requirement, because no weapon should require 100 skill, and I'm greatly increasing the penalty for this (which was like nonexistent in the default game) . . . so, if you don't have the required skill, you're going to waste a lot of ammo.
But what really needs a de-nerf are the energy weapons. Now I don't know if you tackled those yet since, like I said, I'm almost exclusively using guns (and grenades) but the general opinion among the community is that they're pretty much useless when compared to guns. A lousy 9mm pistol is more effective than a laser pistol and IMO that should be the other way around.
The Laser Pistol is actually the first weapon that I've modified, so I have been using my own version in my own game for a couple of days now . . . and mine is no longer nerfed, but now it feels balanced. Lets see . . . what exactly did I do?
Ok, here it is: I set both the Base and Critical damage to 16 (up from 12); I set the Fire Rate at 3 (up from 1); and even gave it a little Kill Impulse kick (so your victims no longer look like they are just inflating). What I did seems to work really well for me. Now if I can just fix the rest with this same sort of balance.
3) Melee for NPCs, Boone two shoted Nightkins in melee with rebar club (repaired to max with repair skill 49), while I could empty clip after clip or 10mm or plasma pistol (skill 40 in both energy and small guns). Another example is Tire Iron for convicts in Primm did more damage to my health then them shooting with 9mm pistols.(I was wearing 7 DT leather armor that I bought from Chet in Goodsprings) Nightstalkers (normals ones not the ones near Jacobstown) seems to one/two shoted me if hit in the torso or head, not sure if they are just powerful and trait small perks makes my head injury that more important or just out of balance. in any case it seemed weird to me.
Melee is a problem, and it is going to be a challenge to fix in a balanced way, that doesn't nerf the NPCs who use melee. I'll see what I can do . . . at the very least, I'll reduce the DAM on some.
P.S.
Powder Ganger Guard Armor reduces max carry weight instead of increasing it.
Thanks. Hmm, I'm pretty sure I fixed that in v.1.3 . . . are you still seeing this, with v.1.3?
After your armor changes, guns feel pretty good. Shotguns are still pretty worthless due to how DT works. With NVSE you might be able to work on a system where DT < 10 means they get full damage, DT over 10 means they do normal, DT 20+ they do 1/4? That way, against lightly armored folks (leather, raider, etc) shotguns would have a very high DPS indeed, whereas against someone wearing combat armor or above, not much at all. This would not only make them more viable, but more realistic as well. Leather doesn't provide any protection against buckshot... (that's literally the point... buck... shot...) Actually an easier and just as flexible model would have shotguns look not at DT, but at armor type, as with a low penetration ordinance like buckshot the material type is the most important factor.
DT is tricky . . . MUCH more difficult to balance than AR . . . I'm probably going to add Threshold Resistance settings to my options menu. But I might try scripting something like what you're suggesting as well.
Energy weapons need some love across the board. There aren't as many varieties, they do less damage in general, fire slower, etc. I don't really like the idea of giving them straight numbers buffs, because then they would just be guns with fancy animations and worse iron sights. They need something to do something to make them unique. Perhaps after hitting a body part, they gain a significant damage bonus with each subsequent hit, as that area 'heats up'? Maybe they are more much more effective against metal and power armors? A straight negation of X% of DT against all armors? I dunno, but with all the creativity here in this thread we should be able to think of something.
They will be getting some love, as I happen to like using them. 
The issue with the above implementation of shotties is how would you make them work with armors added by other mods? How will the game know what my character is wearing? It could APA version over9000 or it could be a string bikini. Even in the default game shotties aren't very useful till you get the Shotgun Surgeon perk so if you're using them I recommend getting it.
I'm not finding shotguns to be nerfed . . . the single shotgun has a base DAM of 50, which means that with 50 Guns, you will inflict 63 DAM (and at 100 Guns, you'll do 100 DAM). Yes it is slow, and the spread is sort of high (like it should be), but Shotguns are not really meant to be used for long-range shots.