Riot knows...
That you guys are absolutely out of your god damn minds if you are making posts about mages as a whole needing buffs to cover the areas such as defense, sustain (healing), and DAMAGE. I know this post will get down voted by all of you low elo mid mains, but still I would like to remind you. Mages aren't that weak to start off. They are, and always will be meta, just like you claim ADCs will always be meta (even though s1 they weren't unlike mages).
Mages don't need extra defensive options. The whole weakness of a carry is being susceptible to damage, which means you don't need to be negating a bunch of damage. Imagine if you guys got what you wanted. I see what you play, you play Lux, Ahri, Viktor, and a lot of other traditional mages. If we introduced more mage defensive items all of these champions would be out of meta because champions like Swain and Vladimir would be even more unkillable, making them the better option. It would also be unhealthy because you are already giving a role something that it wasn't intended to have. Another reason you should stop complaining about defense is RoA and Seraphs. RoA offers health, damage, and mana. No marksman geared item offers health, let a lone mana along with it. I don't actually have much to complain about for Seraphs though, because it is the AP version of Maw, which just got placed as a viable option for marksmen.
Mages don't need sustain, again this is basically the same as defense, but also the reason for complaining is "the other guys have it" (marksmen). Marksmen unlike mages have to constantly get in auto attacking range to deal damage, this puts them in the middle of danger making lifesteal necessary. Mages with as much sustain as an ADC again would lead to a meta dominated by the ap bruisers such as Swain and Vladimir.
Mages don't need more damage. One cast, mostly lasting less than a second is all you need to release your not only damage, but some kind of utility spell. Most mages aren't just damage dealers, they offer up some creativity in how they deal damage, but also offer up a lot of utility, making them better in a lot of aspects than ADC.
'Nuff said, stop bitching mage mains.