How would I know how to make your composition better?
All I could tell you is what I would do if I were you. I guess I could do that.
The 2 examples you state about the oboes and chords are very general. And if you are aware of them then go ahead and make the change.
Trust your own ear not someone else's. If you want someone to rip this apart there are those who could oblige on this forum.
Why numb your own voice by someones corrections that have a different taste?
State what you may feel is wrong with this composition and see if people agree or not.
If your concerned about more technical or theoretical rights and wrongs, that's a bit different.
It's your canvas, paint what you want.
Again, I really liked it! Would I do some things different?, sure!, I'm a different composer.
Let me know what you think.
Michael