IMO, if you're enjoying working on the mod, you should do it. Other people enjoying playing it, too, is just icing on the cake.
I made my Hypermaze mod to try and overcome a difficulty Suicide Junkie (IIRC) encountered while making his FTL map. I've played my mod numerous times, and have gotten feedback on it from all of two people. I have a second mod that I tinker with on and off that may never be "finished" enough to release, but I still work on it because modding is fun.
