I don't think any City fan would be too unhappy at weakening Arsenal or seeing Sanchez at City, but I agree our forward play last season was good when Jesus played. We've since added Bernado Silva, and if we ever sign some full backs, you'd have to think they'd get forward more than our full backs did last season (Navas excepted). The biggest plus point for Sanchez is his leadership.
Even if the window shuts and he's still a Gooner it will be season long speculation. David Hytner the Arsenal correspondent in the Guardian was talking today about bayern coming in for him in January. Then you will have all the free-transfer links. There's going to be so much baggage for Arsenal if they decide to keep him for 12 months. If I were them I would sell and replace him. They are going to have to do it in 12 months anyway.