I may be in the minority, but I don't think we'll sign a striker tbh. I don't think we'd pay the amount for Kane or Haaland. I think Sterling may get games on the left or right depending, but he needs to improve or spend time on the bench.
Grealish can be better than Sterling on the left imo. Not as much pace, but seeing how we play and attack slower at times he can keep the ball and create more with link up play to put balls into the box. He can do similarly to what Mahrez does on the right.
For Sterling he really needs help in someone playing the ball to him quickly and closer to the box for him to be effective. He's not at his best out wide and further away from goal. I think the way which we play in a slower fashion leads to him not being effective.