Honestly I don’t think the mix is the problem here. Sure we can nitpick some things here and there but to my ears the mix and mastering is fine. The two main problems I can see here are: 1) the track lacks a clearly defined structure, and 2) the heavy drums just don’t fit that well with the soft folk instruments.
Tracks like this need a clear beginning, middle, and end. Instead with this track you have the same drum beat throughout the whole thing while different instruments take turns playing 8 bar phrases. No real intro or outro either… the whole thing ends quite abruptly. Also in the middle you have a key change from major to minor which just seems really out of place.
As far as the percussion it sounds to me like your drums belong in a club edm track, not a laid back “farm” style folk song. The samples sound pretty good to me but they just don’t fit this style at all. Personally I would go with more acoustic sounding percussion.
So my main advice would be to study tracks that are already on the site and figure out what their structure is (what sections do they have and how many measures is each section). After doing this with a handful of tracks you will notice trends and patterns which you can use in your own songs. Also notice how almost all songs have continuity throughout with a consistent melody; it’s very rare to have a key change because it makes the track much less usable for the buyer.
In the end, always keep the buyer in mind… it’s tempting to do things that you might think are musically original or interesting but at the end of the day we’re making this music for them and it has to fit what they’re going to use it for.