I honestly would really consider not changing a thing. It's never going to be perfect, and it sounds stunning as it is, so ask yourself, do you really think you can go further with it? or are you just looking for more changes to make. If it's the latter, then leave it as it is thumbsup
Regardless, do NOT change the drum sound. They sound absolutely brilliant, making them wet would be an absolute crime
And I wouldn't change the acoustic guitars either, as some are suggesting. In a poppy/country track like this, they don't need any real bottom end, the kick and bass are providing that, all you want from your acoustic guitar is for it to just neatly cut through with the percussive strumming sound, and that slight shimmery hi-mids/top end. Which is exactly what you've done, and it suits the track stylistically, so I wouldn't bother messing around with it.
The only thing I think it's worth you messing around with is the vox verb, but I would still maintain the stylistic choice you've made there. I would keep the same verb too, I think it sounds cool. I would just work on clearing it up a bit with some EQ, and maybe a gate also, to cut off some of the tail at the end of each vocal line might sound quite cool.
Anyway, when the EP's done, if you're going to be selling it, I want a copy! thumbsup