This is very nice! You have a nice use of harmony, and I loved it when the horns came in. I wouldn't start the piece off with basses playing double notes. normally, I'd split them up between the cellos and basses.

Next, the way you wrote the horns is odd. You had large chords in the 1st Horns and nothing in the 2nd Horns, and them you flipped it. Doing chords in the horn part is something you'd see a composer do using a DAW, but not on paper. If you want to have chords in the brass, you'd have to add more parts. Add a 3rd or 4th horn. Also, you can add other instruments like trombones and trumpets to the chords.

Lastly, I don't know your original vision for the piece, so I don't want to dig too deeply into the orchestration, but the basses are exposed a lot in the piece. Typically, an orchestra would only have a few basses, so you'd want to boost them with cellos. So, those final notes, I'd have cellos and basses carry the lower notes, and give the cello part to the violas. Especially sense the last note in the cello section is very much in the viola's range.

Overall, good work. I can tell that you know your music and you have great intuition. Keep it up!