It seems a difference between you and me is that when I hear melancholic and/or depressing music, it actually fills me with positive energy

Off-topic, but - that would explain why so many people have a kick out of songs that make me want to retreat to my safe place in terror.

I hope this response doesn't sound like I'm getting defensive or anything

It doesn't, and also...

I'd rather try something slightly different and fail than just make something like everyone else.

You don't have to justify what you do.

I think there's a bigger task before you than it was before deadmau5. He wanted to create something that's a mix between Dota's and his style. You want to create a story out of things that happen seemingly sporadically and for people to care about it. I'm not saying it's impossible. I will only personally attest that not everyone's going to look for that because of how some people play the game: to relax, to have a fun hour-or-so. There is also the fact that you don't have enough control over the sound design that the game engine employs to weave the narrative, which is a shame, because with the kind of music that you create, one can really tell a story. You should keep that in mind as you go along.

I wish you all the best on your journey. I hope it turns out well for you, no matter the result. If you ever publish the pack or the music from it, do give me a link to it: I'd like to see what it turns into. And if you ever need another perspective, I'll happily lend your music an ear.