Just limit the height of the minerets.
None of them can be over the height of a cathedral.
Put some other sensible limits out there.
Not likely. When Muslims build their mosques in towns or cities that have churches, whenever possible they make sure that the minaret is higher than any church steeple. It is their way of visibly demonstrating what they consider to be the superiority of Islam over Christianity. I have seen this in numerous places in the Middle East, in areas that are traditionally Christian. They are very adament about this.