I have to agree with C4 on this. All this work, and your other work is very contrasted and it's not easy on the eyes.
Your Trips piece doesn't look too bad, even saying that. Could use less contrast, and the text could really use some work. I found myself really looking at the text, to see what was there etc.
The Kennedy one - awful. I think I can see what style/theme you were going for, but it's awful. Too difficult to make things out.
Orton - The "lava" background/effect looks cool, but I think it's overdone in this. I actually missed the second pic of Orton in this, because of it. I think it would look awesome if it was just on Orton, and the background was black (or darker, atleast).