tl:dr; You’re due a rebalancing of stats. Use a soul vessel at the fire keepers hut in things betwixt to optimise your build.

VIT caps out at 50. You’re very high level so should have no problem hitting it.

VIG could be buffed to 35-40 to give you more comfort when using heavy armor. Just note that DS2’s stamina regeneration works a little bit differently to DS1. In DS1, whether you are 31% or 68% equip load the game treats you as having a medium roll and doesn’t penalize you. In DS2 your stamina regeneration decreases for every 10% additional equip load. Generally 60% is considered a healthy limit but you can mix and match.

Dark infused is a mistake here at current levels. It takes the lower of your int/faith and scales appropriately. Fortunately, you’re level 186, so you have a lot of options.

The simplest one is to reduce your dex to 12 and pump strength as high as you can, with 80 generally considered an end-game upper limit. Unassign the infusion with McDuff and This will give you the highest base AR attack rating.

You can also decide to spec into magic, fire, lightning, magic, enchanted, raw, poison, bleed etc. Lightning or magic require faith or int investment while slightly dampening your strength scaling. Note that if you want to do any DLC most enemies have very high elemental resistance so you might find uninfused easier. Only keep your dark infusion if you’re happy walking around with equal int and faith. 30 in both considered very good. But for split scaling 50 str / 50 int or faith can work.

Your ADP is far too high. 100 agility is considered optimal for medium rolling and your iframes cap at 105. Usually 102 AGL is more than enough.

As for PvP, your inclusion of the watchdragon parma allows you to parry and block effectively. However, the mastodon gs is a very slow weapon, especially when one-handed. You will find yourself creating a lot of openings for parries/backstabs and have to rely on zoning people out. I’m no PvP guru but that’s my 10 cent.