Dude, stick with this. You're already farther than the vast majority of the human race would get in months, and you've worked on this for just over a week. If you can't find a tutorial, take from pre-existing systems that you know work.
I can't say how to turn this in to code, as I'm not that well-versed in C#, but here's what I've gathered you need:
1) A rotation system. This could be based off of movement system.
2) A mirror. This would probably require a new prefab, which is the original object mirrored. You could factor rotation into the mirror, that way you don't go from a slanted triangle to a mirror at the default rotation.
3) A morphing system. The easiest way I can think of to do this is like Reassembly, as in you have multiple prefabs, one for each size; a 1 by 1 square and a 2 by 2 square are not the same thing at all, but rather two seperate objects, where one is accessed by the other.
Also, don't worry about graphics. Once you have everything the way you want it, then start in on actual graphics. For example, let's say you add missiles. At first, these would probably be just boxes. You could name these "missile_placeholder", or name the graphics "missile_placeholder", and either would work to remind you that something needs changed. And I'm not saying get rid of your space cookie, but if you start adding planets, make them circles that are all one color, until you've figured out how you want them to work. Then make them look pretty.
Does any of this make sense? Or was this a wall of text so dense even an anti-matter bomb couldn't penetrate it?