I think Eze will have first spot secured in Arsenal quite soon. He will not be 90 minutes man there but he will play 70+ every week. Gyokeres has perfect storm at the moment with Havertz injury and penalties. Only problem is he was nowhere to be seen in first game. He touched his hair more times than ball as we have seen on many memes 
Sure he will, but he probably won't be getting set-pieces. In Spurs he would, so he'd be a safer pick.
Also, in Arsenal he'll be rotated more than he would have been at Spurs.
Then again - more chances of getting contributions in a better team.. Then again - less time on the ball due to quality in all areas of the pitch.
I will surely skip him for now - I want to see how he fits into the team. If he went to Spurs, I'd trade him in immediately.