First time mastering advice

When mastering, you need to remember that a little does alot.. eg. A 4db bump in EQ on a single track vs a 4db in EQ across the whole mix will produce vastly different results..

If you find yourself wanting to do alot in the mastering plug-in, stop what you're doing and go back to the mix.
 
if you want more verb on your cymbals, add it in the mix. Mastering reverb should only be used if something really needs it (and you don't have access to the mix), and usually shouldn't be applied to the entire track. The only time I ever used mastering reverb was when I was mastering for this punk/metal band, and they were going for that super raw guitar sound, which is all fine and dandy, but the guitars desperately needed a touch of reverb. So I used ozone's mid-side processing to apply a bit of reverb only to the sides, where the guitars lie obviously. Applying reverb to the entire mix would be a serious mistake.

Also, a tip with ozone, DON'T use that damn loudness maximizer, it sounds like garbage. I only use ozone for mid-side processing and because its exciter is multi-band. Just about every other aspect of that plug-in is useless IMO
 
Holy shit that mix sounds amazing, and the musicians are outstanding. Would it be possible for you to post an isolated mono guitar track so I can see what it sounds like?
 
I use a very small amount of reverb on the master bus, almost always in fact. I am far from being a professional though.
 
that's normally something for you dude.. but in that first riff, those things that sound like muted strings being strummed, if they're supposed to be chuggs, then yes. the HPF is way too high. What have you got it set at?