TL;DR below
The issue is that you shouldn't have high sustain unless you are high DPS or a tank with higher resistances.
How does Riot try to balance this?
Offensive items offer sustain to accomplish high dps with sustain (as they should)
Defensive items offer sustain to boost effectiveness of resistances and prolonged fights (as they should)
Avarice Blade is a core item on either offensive or defensive-type champions versus others (questionable)
New runes offer all champs increased sustain *in ALL trees minus sorcery* if you desire to have more sustain. (sort of bullshit)
End-Result: Everyone can get plenty of sustain, damage, and defenses, everyone gets avarice, and the idea of building items for more sustain is pointless.
Riot likes to incorporate a lot of attributes into champions nowadays, rather than defining them into one or two play styles.
What I believe is that Riot needs to make tanks more focused on champion-strict abilities/stats, and bonus resistances with regeneration. There should only be a few HP items existing in the game, I STRONGLY feel. Itemization and runes are much too diverse, even while I do find this season's rune sets the most 'interesting.'
Cost for basic resistance items (like cloth armor) need to be slightly increased, health regeneration items need to be more diversified for TANKS according to play-style (sustained dps, engage+damage soaker, etc..) Bonus Health needs to be limited strictly to bonus health items, not offering many other stats (due to how stat-rich and efficient resistances are, especially while building more health.)
Life steal for Bloodthirster could be nerfed towards low-health targets, but increased towards targets with higher current health to more define its nature of being built on bursty champs (because DPS don't build this shit unless it's ezreal/draven).
Small changes like these are examples of how Riot can define the game a LOT better. Not to say this is 100% what they need to do to balance, but similar approaches towards items and stats. I feel they've over-buffed offense because defense was too efficient, but they didn't question this in the beginning. All they needed to do to avoid this was balance the defensive itemization a LITTLE better and define items towards tank dps/bruiser/initiator play styles.. Cloth armor has been 300g for how many seasons now, yet they change long sword price, doran's blade price, lifesteal price, armor penetration effectiveness, etc for no backed-up-by-our-balance-team's-knowledge reason.
TL;DR tanks were the issue in the first place as Riot fails to define items into specific play styles by instead offering many efficient diverse options for tanks and bruisers (Can get away with building health, building resistances, plenty of damage, lethality/armor shred, max CDR, and still have 2 item slots left for maybe another lethality item or avarice blade. UNACCEPTABLE FOR BALANCE. This is why carries are a little too strong at the moment, but hey, so are tanks. It's just a matter of selecting a good rune page and grabbing a lead to build those items first.
This post was edited by EnigmaSeven on Jan 17 2018 07:55pm