Hi Jens

I listened through your tracks. It seems to me that your guitar tones are pretty thin sounding - for example, on Song 11, you have definitely scooped the mids out to the extreme to get that hollow sound. Which may or may not work for you. The drums also are lacking in both volume and low frequencies.
In Try to Catch it, the vocals have a very obvious reverb on them as well as some recurring sibilance in the verses. I suggest eqing out the sibilance and either adding the guitars into the same reverb or perhaps coming up with a similiar reverb foir the guitars so that the vocals don't sound so separate.

agreeing with eds1275 here, especially the drums. Because drums typically drive the song, they should be well EQ'd and provide a base. Then i would EQ guitars and bass and vocals off that.
However, if that "hollow" sound is what you are going for, you'd still need some low-end in your mix. Don't let Mastering try to do all this for you. Mastering is the process that can give most songs that similar "punch"