I've worked on several Unity projects as basically sole gameplay developer at my previous jobs, but they weren't really games in the traditional sense. This is my first real game project, and that's reflected in the fact that I chose to build my own engine XD I thought using Unity would be overkill and there's no sense in paying them in case my project becomes a financial success. But looking back it would've saved me like four months of work, so I advise anyone starting out to go with a premade engine, especially since there's free ones like Godot.