Were I looking to go this route, I'd certainly want to consider reversing capability and perhaps a bit roomier cab to allow for the possible addition of R/C. Also oscillators are a bit tougher to successfully route all exhaust steam up a stack, though this guy obviously did a fantastic job of it, but still, I'd be looking at basing mine on a Jensen 75 I think, as that would offer reversing, with a bit more power. Better yet would be a Jensen 55 style twin cylinder set-up, as that would also offer self starting and much more power!
However, for a first effort, maybe this really is a better way to go.