I don't know what to say about him.. He is the only mage i ever wanted to play if i have to go mid ( im a supp main ), yet i just feel.. useless with him.. If i miss even a second and walk to lane a second later - almost my entire laning phase is ruined, since i can't place 3 turrets fast enough to prepare..
Even if i do go mid the moment the fountain opens , at rank 1 Q feels weak and die fast. I feel strong for several levels vs melee mids , but the moment they get their MR AD item, they have 0 problems destroying my towers easily and kill me. His kit revolves around his turrets - yet if they are made strong, people will cry and he will truly be OP.. if they are not OP - they are useless... Nowadays the game has so much damage that even melee champions manage to tank 3 turrets and minions , while delete me for 2 seconds .. After laning phase ends - in teamfight its very hard positioning all 3 turrets on a good spot at any moment.. So i have to rely on W or R+E , which is somewhat hard to hit, with very very high CDs..
I see now they play him tanky Heimer with ZZ, banner, Zhonhyas .. sure in the scenarios where you are left free to splitpush it can work .. But its totally useless in teamfights - i've tried it .. Extremely low damage to champions, which is hard and unreliable to pull off with tank build.. His pure AP is strong if ahead - but then, who isn't strong when ahead .... To be fair if i want to splitpush as mage , Ill just take Ziggz and 2 shot towers ... I will also have insane poke , AoE, good waveclear and absurd burst damage ..
Also people are smart enough now to avoid / destroy his turrets or can even afford to take the damage and still 1 shot me if i don't have zhonhyas ..
I think he has his strenghts , but it's not a viable/prefferable choice - like Ahri , Viktor and etc for mid ..I've seen heimer being picked top vs the melee champs , but still.. if his team is falling behind, Heimer is not the type of character to solo carry a game.. Unless he manages to splitpush and hope enemy team are clueless.
Overall he is either too obnoxious to deal with or is in a hibernate state..
**TL:DR **I would love to see him totally, completely reworked.. As a scientist , maybe have some form of Towers/Inhibitos/Minion wave/Cannon minions control.. any or some of those stuff would be lovely. Maybe have the ability to switch off a tower or make it harder for a time ( simillar to Bard ult ) .. Maybe have some form of tower repair.. Or the ability to make tower hit the target he chooses for her when at range.. Anything which tweaks the mechanical/robotic/technical stuff in the game.. For example i have a much easier time imagining Azir's passive to be Heimer's .. it just makes much more sense... Why is a sand pigeon emperor with a spear able to create a tower, when a scientist who WORKS in that field is not ???!!! His Q turrets creating is very cute and an amazing idea.. but either doesn't work in the current age and day for LoL's shifting metas and standarts or are just extremely toxic to deal with ...