Welcome to the forums.
Yes...that can all be done. If you look in the archive of the blog posts, around Halloween and Christmas every year, there are projects involving active decorations. At least some of what you want to do will be in those posts. How to do the rest should show up in either blog posts or issues of the MagPi magazine (they're on line and downloadable).
Through the USB ports, a Pi3B can supply up to a total of 1.2A at 5v if you have a PSU for the Pi rated at--or a bit above--2.4A.
My suggestion would be to develop each effect separately and once each works, then combining them.