Requiem for String Quartet

So, I completed my Requiem for String Quartet about 2 months ago. Figured I should get some feedback on it. This is the longest piece I've composed for a String Quartet. I eventually decided on calling it a Requiem instead of an Elegy because of the drama. From the Dies Irae and beyond, my melody is based on the Dies Irae chant. This is how my piece ended up being sectioned(I didn't bother with the Santus and whatnot, because when I looked at Requiem structure, I mostly got Introit, Kyrie, Sequentia as the structure and then the breakdown of the Sequentia into it's component parts, plus, it was instrumental and not a mass):

Introit and Kyrie - F minor - Bars 1 - 13 - 0:00 - 1:06
Dies Irae - C minor - Bars 14 - 39 - 1:07 - 1:51
Tuba Mirum - Ab major - Bars 40 - 105 - 1:51 - 4:38
Rex Tremendae - D major - Bars 106 - 113 - 4:38 - 5:24
Recordare - Starts in G major, ends in C minor - Bars 114 - 200 - 5:25 - 9:07
Confutatis Maledictis - C minor - Bars 201 - 224 - 9:07 - 9:44
Lacrimosa and ending cadence - F minor - Bars 225 - 250 - 9:44 - 11:00
 

The Dies Irae, you might notice something about the rhythm of the motif that starts it, it's almost exactly the rhythm from Mozart's Dies Irae. Indeed, it sounds the same rhythmically. Instead of being half notes and quarter notes at 140 BPM, like in Mozart's Dies Irae, it's quarter notes and eighth notes at 70 BPM. But it's the same rhythmic ratio. Here's mine:

And here's Mozart's:

I did listen to Mozart's Requiem almost nonstop for several days before writing my Dies Irae, so I'm not surprised at this rhythmic similarity to Mozart.

When I was writing the Tuba Mirum, I saw 5 groups of 3, I guess measures you would call it in the chant, so I was like "Okay, I will have a solo moment for each of the instruments, and then they will come together in the last group of 3 and start to modulate." Because I was going to the Rex Tremendae next, I was wanting to modulate to D major, what I think of as the key of majesty. But I was all the way in Ab major, a tritone away. How was I going to get there? Well, I went one tone at a time, modulating from Ab to Bb, then to C, and then ending on an A chord so that with the next bar, I would be in D major. I harmonized the melody of the Rex Tremendae as a chorale, and you might not be able to tell, but the melody from the chant changes instruments.

When I was getting close to the Confutatis Maledictis, I was thinking that it should be the fastest part of my Requiem, so I put in an accelerando. And the extreme contrast in the text made me be like "Okay, let me make this the place with the biggest dynamic change, what's been piano before will become pianissimo and contrast with fortissimo." And in the Lacrimosa, I used sighing eighth notes because tears. And I was back in the F minor I started in. For the final cadence, I ended quietly, because I felt that was best for this piece, a quiet ending, like death itself.

Here's my Requiem. What do you think of it?

Requiem for String Quartet.pdf

Difficult. I failed to spot any particularly interesting section. Around the one-minute and two-minute marks your piece peaked my interested, but then it all fell flat again. Around the five-minute mark, it gets more interesting again, but only fleetingly so. Around the eight-minute mark, I spotted an interesting idea again.

The problem seems to be one of form. I cannot make out what section is supposed to do what. No clear cadencing, phrasing or organisation of voices, steady pulse without rhythmic interest. Sounds more like a sketch to me.