I wonder how many will take them up on their offer. Two problems. Firstly, when you try to charge for something that had previously beeen free, then takeup is not that high. Secondly when you have upset so many potential customers by messing around with their photos,why should they trus you any more and pay for it. They might come back if it is still free, but unlikely to be prepared to pay anything for it.
Better to add advertising, not that everyone likes it, and many can block it, but easy enough to ignore, as long as it is simple pictures, and not annoying video/sound. They could even make adverts relevant to pictures being displayed.
Alternatively,buy some webspace(it is not that expensive), and you can then not only create your own website, but also have full control on your photos. Group together with others, and split the cost.
Narrow gauge Francophile interested in 1m, 60cm,50cm , 40cm and smaller gauges . Build in scales from 1/6th to 1/24th. Also 1/32nd and 1/35th using 16.5mm track to represent 50cm and 60cm gauges.