You seem to forget his passive... mana item stacking doesnt give ryze much mana, buying ap+mana items and finishing it off with deathcap does.
Aswell as u forget riots mindset, Glasscannon should always be more rewarding then building defensive/safe.
So here bit more then random thoughts on this matter from me (ryze otp btw :D) :
Ryze as a whole seems kinda weird. His spells and spell interactions + stat values and effency kinda make it seem as if ryze has not found his own identity while searching all his years for the runes.
Speaking bluntly the only reason for mana on ryze is his passive (mana "scaling" from ap) in combo with archangel which gives him extreme high ap values. The mana ratio on his spells feels just bad and not rewarding (u dont say wow i got 5k mana i deal tons of dmg) and because of the extreme high ap he can have, the ap ratio in general is lackluster aswell (most other midlane champs have higher ap ratio).
in addation they gave him good burst/combo dmg with q reset and e+q interaction so that his first combo can literarly 1shot most carries (thats why the most common build is abyssal mask, zhonyas, archangel, void, deathcap). As a fact ryze is nearly unbeatable in midgame cause he is able to get double resistance which negates most dmg 15-35 min into the game and once completing archangel has more ap then his lane opponent (if his lane opponent is an ap champ).
And so that ryze is not unbeatable lategame aswell they made his sustain/utility useless. It scales with champion lvl, not ability lvl, it has bad base values and the worst is that it comes with a major downside. Losing the 2sec root or 40% of ur dmg for a ~300 dmg shield and 40% mvspeed is more often then not the bad choice.
Having the time to cast ur e twice in any teamfight means the enemy is doing sth majorly wrong. And the e wont spread anyway... its not happening, maybe once from 100 total teamfights and then it spread from the tank top to tank support (yeah !!) and the spell iteself deals absolutly no dmg itself. so doing this for the shield instead of using q for more dmg is not only the bad choice, its an unbelievable bad choice.
And to make all matters worse, more often then not the actual shield doesnt really do much, because if u run up to someone to combo him, he will open fire immediatly... so his dmg hits ur hp... and after that u get this nice shield which absorbs the 1spell or auto they throw after you while u run away with 500+ mvspeed (if u run in say goodbye because god knows that ur shield wont save u from anysort of focused fire or burst dmg).
To top it all off they gave the runes a low cooldown with no way of charging them some time before engageing. You can only charge them on minions or champions... if u charge them on minions u have to flash on the enemy so the runes dont run out and if use an enemy champion to charger ur rune, u are more often then not dead before u could proc it. And the most fantastic thing ever is, they give u a q reset on w and e, but wait they made it so that every q discharges the rune completly so if u use ur q reset everytime ( q,w,q,e,q) u get like 200-250 more dmg in ur combo and dont get ur 300 dmg shield + movementspeed.So his shield/rune mechanism makes absolutly 0 sense with the gamestyle he has atm. He needs a shield to begin the trades, not end them.
The most reasonable thing riot could do to make this oneshot/combo ryze better, is adding flat (maybe even true) dmg on the q if it uses 1 rune (dmg is applied last so no double dmg for this on e+q), since it uses up the 1 rune anyway. Aswell as make it so that the runes once they are charged, stay charged longer (charged = 2runes) . This can be a passive on his ult. This would make his full commitment to the combo hit harder aswell as making his roaming/engage straight up better.
If they want ryze to be more of a fighter they just need to make it so that every spell charges a rune and only the full charged rune discharges on q. So more or less how the "rune/passive" stack used to be. Sth like 3 runes max, but q charges a rune aswell --> only if u go full cdr with some defensive items to stay in a fight u get more shields then now.
Atm its q,w,e,q or q,e,w,q for first shield then e,e,q 2nd shield and w,e,q for 3rd shield (~ e has=1,5sec cd and w=5,5sec --> 3 shields ~ 8-9sec fighting for 3x shields) , with the changed rune mechanism the max shield combo would be q,e,q 1st. w,q,e,q 2nd e,q 3rd e,q,w,q 4th e,q 5h. (~10sec for 5shields)
Then they just have to change the passive to sth like muramana passive, no mana ap doublestacking from passive archanagel and deathcap.
So it becames easier to balance the ratios, since most mana/offtank builds end on ~3k total mana and prob ~350ap.
with 7,5% bonus mana dmg (twice for runeshield proc), each 300-400 mana item gives u ~20-30 , archangel gives 75. The max dmg build would still be archangel, roa, morello, void, deathcap, you have rougly same amount of mana as u would have with "tank build" but ~450ap more (~150ap less then now with mana ap stacking passive = --90 dmg less on q and w and 45dmg less on e), but every spell deals 50-100 more mana dmg---> less burst more sustained dmg (since e has biggest dmg+ from mana and it is a point and click low cdr spell) with overall same dmg output as now with full dmg build.
So the offtank build just deals more dmg (mainly cause the build gets 40% cdr with ease and e deals more dmg) while the glasscannon build deals as much as as it does now so that it is still viable. aswell as both being "healthier" in prolonged fights since the shield would proc more often while keeping max dps up.
