Riot before you change Heimer: Listen to this guy

This guy is right. I am also a heim main, and i can tell you that half the mid lane matchups (where you intend to move him) are complete crap because of his turrets. However, if you go with these current changes, you will incentivize people to max W first, making him a poke champ as Heisendong says. That's not Heim. The nerfs to his early game too make his turrets more useless than ever. If you want people to max q and actually use turrets, try changing the turret stats themselves.

Tweak the HP so that it doesnt scale with heimer's level, rather Q's level. Make it so that the turrets have enough tankiness to not get obliterated in laning phase, but still don't have enough damage to make the other laner want to kill themselves. Also, don't overdo the scalings. He doesn't need a 35% ap ratio from 15%, because in lane a liandrys can more than make up for the base damage nerfs even if he doesn't max Q. IMO, bring it to 25% and nerf the HP scaling with AP while buffing the base HP of the turrets per Q's level.

This way, instead of always maxing W, a Heim player can choose if they want more siege and sustain in lane, so they max Q for turret survivability or do they want more poke and damage from turret beams, so they max W for its CDR and beam procs. I get it, the new W changes make him viable midlane with poke and all. But his turrets deserve some love too, especially since his identity is built around.

TL;DR The current Heimer changes on PBE are forcing Heimer to max Rockets over Turrets, which completely changes his playstyle in a way that just doesn't feel like heimerdinger.