Flight Of The Toolator I would say was very well done. I enjoyed that M2 stock map and this one makes it a whole lot better. One Hit Wonder is definitely a huge change, and improvement from the original. I do agree with the previous comment though about adding some details for the level modifications.
I do enjoy the very unique design that these levels have which certainly adds to the gameplay, and, not something you see in older Marathon Maps. Maybe one issue is similarities some levels have like the corner areas (for lack of a better term)of Paradigm Shift and Oculus Ex Inferni. The Downfall Of Paradise, I think is the best one.