So I did the thing again where I said I would stick to an engine and mechanics I was comfortable with, rather than trying to learn new stuff... And then I decided to make a first-person game in Unity, which is very new to me. It's gonna be a pretty small walking sim, with some basic text narrative, so I think I should be able to manage it. Anyway, here are some screenshots of the gray-box I set up today:

Most of the updates so far have been back end, so not much point in posting up to this point. I abandoned the First Person Exploration kit as it wasn't doing exactly what I needed, and it felt faster to just script it myself rather than figuring out how to work within the FPE assets. Movement, item pickup, and menu navigation are all working, with the last piece of scripting being a basic dialogue display system. I also started messing around with the lighting and it kinda looks like a game now? Obviously still a decent amount of modelling left to do though.