If by "boilerplate" you mean creating/registering a window class before creating a window, you don't need to do that if your application's UI largely looks like dialogboxes - DialogBoxParam will create a message loop automatically and all you need to give it is the layout template and the message calback WndProc.

(I've been working with Win32 for around a decade now, it's got its warts but really isn't that bad once you get used to it. You can do a lot of interesting things with it.)