fire is next to useless in hell
hybrids are characters for idiot players dont use them, take a starting char with shit damage and lower your output damage by half == hybrid sorc damage there you go
if you are in an area that you do find an immune monster consider that a sign that you should not be mfing in that area
when you start out on ladder you make a vita bliz sorc and it can mf all hell bosses, ancient tunnels, mausoleum / crypt, summoner, trav / clears chaos fine with static + merc stomping mages / nith / baal (same method)
it does not take long to find hrs in chaos
then you make a light sorc with infinity
there should never be a time playing d2 that requires a hybrid sorc of any build unless you wana be laughed at or stay poor