If you want my two-cents, I'd suggest coming up with some actual gameplay ideas and mechanics to utilize. The gameplay should come first, and story/aesthetics second.
Hell, that's particularly why there's one project of mine that's still in the early alpha phase, because I keep trying to improve upon my gameplay and mechanics ideas. I've gone through at least 10 design iterations since I started the project this time last year.
No. Don't encourage him to do something he has no experience with getting himself in to. You'll only be digging him a hole and literally pushing him in there to never get back out.
What he needs to do is not take on a big project before he is capable of taking on a small project. My advice to you is to do something more your size. Think of it as a woman and a man. You can't take everything on all at once. But, seriously, start small. I can't stress this enough. I just had to tell someone else this earlier. And not to mention 3 days ago as well. And yesterday too now that I think about it.
You'll just be spending 10 years of your life trying to do something that can take a month to a year to even get started if you just put in some practice.
Choose a game engine that fits your taste and purposes (do research to find out which engine has the features you need). No one engine does it all. I prefer Unity because of how simple their UI is. But, Unreal Engine has easy networking and some nice shaders out of the box. While UE has nice shaders and networking, Unity has a new Networking system coming out soon called UNet. It is a part of Unity 5.0 and, from what I am told from a certain someone, It will be in Unity 5.1. Not only that, you can program your own shaders in Unity.
So, it all depends on whether you want to be lazy and have your shaders set for you, whether you want your networking done one way or another, or if you like the difference in performance feels between the two. Your pick. Choose wisely because you should be putting in extra practice with the one you choose to get really good with manipulating things, fixing bugs, and producing small scripts to be reused in other projects to save you time.
Once you've learned your way around your newfound engine, utilize scripts from other projects you've done (even if it is just the logic) and try implementing them in new projects that you'd like to take on. Remember, keep them simple at first. You don't want to burn yourself out.
Hell, that's particularly why there's one project of mine that's still in the early alpha phase, because I keep trying to improve upon my gameplay and mechanics ideas. I've gone through at least 10 design iterations since I started the project this time last year.