You can never get rid of wagons in the city; the goal must be to reduce their use, and for that I think you must convince people that they don't need to own one, because if they do, they're more likely to use it, since the fixed costs are large compared to the marginal (per ride). And to convince them of that, you'll have to make them trust they'll have an available, affordable and comfortable alternative for those situations were they really need one.