Bro i have literally the worst gear and i can still do hellruns in like 25 minutes average.
I have only 37avg grudge, i have belt+6 only, and I'm still at my 94 bio...
for alchemy i have a perfect ruby, skill res diamond, hp% jade, block onyx. all minor.
I do like 9.5k dmg on boss and i still do the run in around 25 minutes every time.
Just push yourself with skillres and you should be fine.
I have a skillres pendant, 5 in shield, 5 in armor and thats enough
also I use bane throughout the whole run to kill agnis faster.
i still can tank 7-9 hae taes at the walls with using instant potions and rarely die.
Just make good use of /set_r and step to the walls before the hae taes attack you and there is basically no way to die in that run
If anything, Hellrun would need a buff. And I've seen part of your gear. I have literally no idea how you can not make the hellrun.
Idk how bad your computer is but metin really works on almost any setup.
Idk man, I just don't know...