Joe...Here's my thoughts on the tracks you posted:
Trekked - Good solid riff to build a song on. I can hear a lot of drum and guitar parts that would go well. It could go off in a lot of directions, so there's not much to say, but I like the style and it has a lot of potential. The main riff has the kind of feel I like to play when I'm jamming by myself at home.
Tracer - Beginning riff is cool, goes on for a bit longer than holds my attention, but it might be different with other instruments and vocals. I like the middle section after the stop and go part. I can hear a good guitar solo or vocal part over that. I imagine some great drum fills in those rhythmic gaps, I like the concept. I think I would like to hear the beginning riff branch out a bit, if there were guitars over it I'd say have them keep up the basic riff and have the bass part work some harmonies. It works well for the end of the song as is. Although I could hear the faster part at the end being at the beginning of that section and ending with the slower part instead.
Desolate - Really bare bones and repetitive, which is not a bad thing for this style. A song like this lives or dies based on the band as a whole and how everything comes together (especially the vocalist IMO), but it's a good foundation. The uptempo part feels like the last note should be something different to me, but it's a good bridge for a vocal part or maybe guitar solo that could be really fun. Although I think maybe it could come a bit earlier in the song, dunno.
Some really good riffs, sounds like you have some good ideas to build off of if you can find some good players to flesh it out. I'm filling in a lot of gaps with my imagination though, so I'm sure it could come out very different than what I'm imagining.