Don't be too down hearted Rob! You're working on something big (as you've told me) and even if it is a bit more niche, it may become a staple in said community. Not only that, you'll have the skills and knowledge to make more, perhaps the skills even spill over into other things :3
Just like with your art; it took a long time to hone it but it's brilliant and I love it very much.
Don't value yourself too much on the general consensus of "success" and keep on doing what you love. It'll work out.