Yeah I know its nothing new, theres even a website where people do that massively, however what I meant is that we're not taking it seriously, its mostly as a hobby and a way to have fun...
Of course its possible to record everything yourself, even if you dont play the instrument since you can easily put stuff together with software like Garageband, however its more fun when there are more people involved, I believe... Honestly I'm a total n00b at all this
And about your tracks, if you link me I'll surely see if there's something I could add, as I said, I'm far from being a professional musician (I'm far from being a musician actually haha) but for fun sake...