In mojoportal, pages are just containers, no content at all goes directly on a page but only by putting instances of a feature on a page. A page "knows" what feature instances it contains, but it knows nothing about the kind of content within the feature or the inner workings of the feature.

So in mojoportal we have 2 different gallery features you can use by putting them on pages. You can have multiple galleries by putting different ones on different pages. I don't know whether either of our galleries will be exactly what you want.

I think an approach I would consider is integrating with Flickr. Image files can be very large so offloading the storage of a lot of images to Flickr seems like a good approach. You would have to implement your own feature module for mojoportal that integrates with Flickr as there isn't one already, but there are several ASP.NET examples of Flickr integration that you could base it on. I think I saw one recently in the Drop Things project. google it for more info.

Hope it helps,

Joe