Yes, i was actually really surprised as i watched your timelapse in discord, that it was made in Unity. Because of the whole look i would have bet it's Unreal^^
Also thought, if i would make this quality in Unity, then probably could make it maximally run on 30-40fps, and with especially this zero-gravity style this would even cause more motion sickness. The more impressed am i actually now, that i did not "feel" anything. So guess this snap-turning was then also definitely a good decision. But if you need testers for smooth turning sickness, I would be open :-)
For the rendering yourself, i would probably go with multiple camera's. Then you could maybe just assign a User-model/rig on yourself. But put it on a separate layer. With the aiming-gun-camera you could render it and show its output then on a texture, which you could place on the screen (what you probably anyhow do already?).
But with the VR camera/s you could just skip that layer. In this way your actual first-person look won't change (and you can keep just showing the hands, what makes most sense i guess), but you could see it from "outside" also. Of course just a quick approach, not sure how performant it is. And in the end, it is absolutely no "game-changing" feature or so. Just thought during playing, that would be actually also pretty cool.
Yes, i also definitely would encourage you going on with it. In my oppinion this IS already better than some stuff you can buy in the Oculus store. So when you add maybe few more puzzles or levels or so and polish it even a bit more, people will love it.