Swinject: MVVM and Storyboard Setup

Question

It is my first project using Swinject and I want to make sure I use it properly.

Coming from a C++/Objective-C background, I don't have much experience with dependency injection containers.

I follow the MVVM architecture, use SwinjectStoryboard and let the storyboard instantiate all the view controllers for me.

Here is my setup:

extension SwinjectStoryboard {

    class func setup() {

        // View Controllers

        defaultContainer.registerForStoryboard(ItemsCollectionViewController.self) { resolver, controller in
            controller.viewModel = resolver.resolve(ItemsCollectionViewModelProtocol.self)
            controller.imageLoader = resolver.resolve(ImageLoaderProtocol.self)
        }

        // View Models

        defaultContainer.register(ItemsCollectionViewModelProtocol.self) { resolver in
            return ItemsCollectionViewModel(userSession: resolver.resolve(UserSessionProtocol.self)!)
        }

        // Services

        defaultContainer.register(UserSessionProtocol.self) { resolver in
            return UserSession(webService: resolver.resolve(WebServiceProtocol.self)!)
        }.inObjectScope(.Hierarchy)

        defaultContainer.register(WebServiceProtocol.self) { resolver in
            return CloudKitService()
        }.inObjectScope(.Hierarchy)

        defaultContainer.register(ImageLoaderProtocol.self) { resolver in
            let imageLoader = ImageLoader(fetcher: resolver.resolve(ImageFetcherProtocol.self)!,
                                            cache: resolver.resolve(ImageCacheProtocol.self)!)
            return imageLoader
        }

        defaultContainer.register(ImageFetcherProtocol.self) { resolver in
            return CloudKitImageFetcher(database: .PublicDatabase)
        }

        defaultContainer.register(ImageCacheProtocol.self) { resolver in
            return ImageDiskCache(location: .CachesDirectory, subDirectory: "items/pictures")
        }
    }
}

A few questions:

• Is it OK to use the defaultContainer provided by the storyboard for everything?

• Am I right to assume that there is no way to use initializer injection for the view controllers and therefore no way to make their viewModel property private?

• In this setup, does it make a difference if I use the .Hierarchy or .Container scope?

All feedback welcome.