I think it's good to put your work out there. Never know what you might feel about a work until someone says something about it.
Digitize definitely has that cyber-esque feel to it. I could see it being used for a level with a lot of baddies and forward movement.
I think Dread could fit in as an antagonist's theme, or maybe as a variant of a theoretical one.
Trouble in the Air is, as you said, a standard boss theme. Maybe more fitting for a miniboss/alternate theme, depending on what you have in the works. The impending nature of the melody suites that mold.
Don't have too much to say about the older works. Most are good and have the same feel: High action, short melodies. Could use a little more variety but overall good job. For what I do have to say: I really like Haunted Garden, Emptiness has some potential, and Rocker has a persistent tune (Good or bad, depending on what you intended for it).