Obviously having a mod manager like you describe would be awesome, but it'd take a lot of work on my end to implement it, and since Steam already has the Steam Workshop which is basically the same thing, I'd basically be wasting a ton of work that will just get thrown out once the game launches on Steam. So no, not gonna happen, sorry. 🙁
gdpr please make a link to a version selection screen beneath the big download button. I hate having to edit the URL to get the version i want from your server.
There's a link at the very bottom of the page.