Lack of Health + MR Items
(if you have healing)
(niche vs matchup)
(limited to ap champs)
Pretty much if you're an AD champion and you want MR+HP, you either get Visage or another full item that gives hp in addition to an item listed below
MR Items that don't give health:
limited to mages
not slot efficient on most champs
limited to mage-supports

limited to tanks/split pushers
limited to supports
limited to tanks/supports
Good item ++, extremely expensive
Good item++, extremely expensive
Good item ++
extremely op and new
Seems like MR itemization overall is kinda weak, while I wanted to specifically mention MR/HP items since there's only 3 that are all niche