Mad respect for trying this, guitars are a pain in the ass to mix. Some tips:
*Double track any rhythm guitar parts and hard-pan them (or pan them 80% to each side for a slightly more natural feel). They have to be wide, and just to get this out of the way, putting down the same take with a slight offset doesn't get the same results.
*Less cymbals/hats! If the highs feel empty, try adding some shimmer reverb (cuts all the way up to the treble, damping disabled).
*Work on your composition; there's not much to grab on to in terms of hooks, and more big changes in dynamics/arrangement would go a long way to give it some life.