however lack of opinions, and overall communication in my subforum, is striking - explanation is simple, either the application is not really needed, or it sucks.
There's a third explanation that I personally believe is the correct one (as someone who has also put his hard work up on the Internet for people to benefit from):
People don't like/want to/know how/care about giving feedback unless
- It is something they feel they need or just feel entitled to have
- That something is broken in some real or perceived way.
Usually the feedback is abuse ("why is this @£$€ broken? You suck!") but from time to time you do get the odd post with real, valuable constructive feedback and/or constructive criticism, and once in a blue moon someone actually posts how much they appreciate what you've done - and that keeps you going for a while longer.
Being a salaried or hourly paid developer is a thankless enough job on many occasions, so doing it for free really is a labour of love. It is also extremely thankless and more open-source and mod developers burn out from the sheer thanklessness of it than keep at it for any length of time.
In the end I think you need to do these things for yourself and not for others - the dissemination of the code to others is just a side benefit for the developer (although it may be the main benefit for others). If you have an itch you need to scratch, that need will sustain you until the code is good-enough for you. For it to be developed further, you need to get feedback (and some praise!) from other users. Otherwise it's usually better to pass it on to a new developer with a different itch to scratch.
What I'm trying to say is that I know. I've been there. It's thankless, nobody's paying you for it, and precious few seem to even care. I totally understand that you just want to scrap it all and move on with something that doesn't
drain you. And it is your right to do so, of course. But this is a small community, and even in huge communities the rate of feedback is minuscule (I just went back and did a quick "comments / number of downloads" calculation for my old ESO addons, and the result was
0.4% - and that's a community in the millions).
So here's my suggestion: Don't burn any bridges, just take a break. Do something else for a while. Leave the Mech Designer up there for people to try, use, enjoy, and leave feedback on. That way you can gracefully come back to it later if the original itch you had comes back.
Any way you decide to go, best of luck to you from a fellow dev who's been there.