AP trist is an interesting one. I think it would be beneficial to Keep the current AP scaling of E, but increase the AP ratio by .02 for each stack of the E Charge. So it gets another .1 to the scaling on 5 stacks. (These are random numbers but yea. The concept is if you charge it the AP ratio will increase)
Tank Heimer was cancer. Fuck that shit. Its one of those things that was just awful to play against. It was on Proxy singed levels of Making the laner want to just quit the game. He would just rush a Zz'Rots and get tanky and all he would do is split push ALL game. It was infuriating to play against if the enemy team could hold their own. And infuriating for his team if he wasnt able to get things done with the split push because they were fighting a 4v5 while heimer jacked off in top laner all game.
AP Jarv..... Isnt that just the shield? Its honestly AP Lee levels of troll build. Its one of those things that sure, they could make it better, but you are probably going to get reported if you play it.
AP gnar is player but its not JUST ap. because the AP is on the W its more of a Hybrid AP AS build which is fine. In its current state is actually pretty decent if you dont get dumpstered in lane due to his low damage early.
AD taliyah...... I need to say something about giving AP champs AD hybrid stuff.
The problem with giving an AP champ AD hybrid is because it incentivizes building AD. Now AD is consistent damage. Because Autos are consistent. And most AP champs are balanced around the idea of burst and Leave. When you give them AD options it makes them overall a stronger champ. We have seen this in the Katarina rework. Im always wary about giving an AP champ AD scalings. I think giving AD champs AP scalings is fine due to them already being balanced around their consistent damage output and adding AP will often be turned into a bit of a squishier bursty champ. But they sacrifice some of their consistent damage that they are balanced around.
Now I will say my favorite off meta build IS and AD version of an AP champ.
I love playing AD Kassadin. Its a bruiser build that relies on auto attack resetting with his W. The great thing about this build is that you become a super sticky bruiser that is near impossible to escape. You just hunt people down and auto them to death. Add in an Iceborn gauntlet and you are set.