Wow Daniel, what a post! That is a truly professional critique! And no, I don't think you are mean.
Yes, I am quite confident in my orchestra's ability, as I have asked a string player within that orchestra about the difficulty, and they seem ok with it. We do have 4 timpani, yes. The tenuto marks on the semiquavers are a sort of emphasis, saying don't slur it, but keep the bow on the strings. There's probably a better way of saying this, but I don't know. And the difference between mf and mp, well as QC said, the dynamics should be uniform in the score, so I just wrote lightly underneath in order to give an idea of how it should be played.
I agree I have to do more harmony study, but I think some of the places where you pointed out "confusing harmony" weren't so, but I could be wrong (page 43 and 44 only).
I also did not notice the parallel fifths in that one part! My mistake

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I'm fairly confident in the performability, but thanks for your comments!
And millyway: I don't know why an oboe would sound comical, maybe its the midi, but I'm sure that in real life, those parts won't sound "comical". Thanks for the post

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