I'm a combat guy first and foremost in an action game. So I'll start from there.

1. I want it to be a shooter and beat em up hybrid (think something like deadpool game/ W 40k space marine games). Without it you cannot feel like john wick. You should be able to switch your playstyle on the fly. Buttons will be reserved for melee combat & left trigger/right trigger for shooting.
2. I want the game to identify enemy's weakspot for you (think rdr2's deadeye or the one we are seeing in gta 6). Because you wanna pull of john wick's accuracy & his "chest chest headshot" maneuver.

If game put some indicator on enemy's chest and head.. And game will give you some minor aim assist when you are locking into head or chest. I think that will make " shooting like john wick" aspacts more easy for us.

Now game can tackle it in many ways. It can be a difficulty thing (easy/normal mode will have that. But hard mode wont allow it).

Or maybe you built up a meter which enable you to see enemy's weakspot for set amount of time.

3) I want game to give us small amount of ammo for our weapons. Because without this restriction player wont engage in hand to hand fight as much as developer wants them to.

So, much like suit for hire game.. Game should encourage player to perform well in order to refill ammo / limit the ammo capacity. Maybe only some enemies will carry gun in most enemy encounter.

But i do want to see some levels akin to john wick chapter 3's continental fight where game gives you a lot of weapon & ammo. Some shooting centric level is needed because john wick films has section like that.

4) Give us a lot of environment objects to play with. It should not be restricted between pencil, cup & books. Give us small things that we can use creatively in battle.

Maybe you found some steel nails. Now either throw at it toward enemy's face or wrapped those nails with clothes/tape in your hand (kinda like wolverine) and use it to maximize damage.

5) Hope we get some driving levels /car combat sections. Slamming other cars & shooting at them while someone else driving can be pretty fun and add some varieties in mission.

6) Game should give us access to reply any level we want after finishing said missions. Maybe we can access them in main menu.

Oh and a scoring system would be dope.

  
I donno at which point in time does this game take place in (its probably a prequel).  I hope we get to see john wick at his prime & hope some of the movie character has a key role here.

  
What do you wanna see in john wick.. Combat /story wise?

Things i want to see in john wick game. (I know its not coming until 2028 but i stil wanna share it. Let me know what you wanna see in it)