hey there!
Alrighty, so I have some comments after listening/reading your piece. I'm a clarinetist, so hopefully I can give you some good feedback.
1) I would have to agree with flint about some of the upper-register writing. The clarinet sounds scratchy and forced when playing anywhere above a C above the staff. You wont see any writing for clarinet like at measure 32, where you have it up in that tessitura range. It's a killer height for a clarinetist, and those spots are usually reached at the end of runs leading up to them. There are some exceptions however, such as the Poulenc sonata where he goes up in that range quite often, but it isn't even for extended periods of time, and is usually just for flourishes and whatnot. giving a long, extended melody up there is a deathwish for your audience

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2) I'll disagree with flint about the repetitive 16th notes at 64. Writing like this is seen constantly in older music, such as in the Hayden concerto for clarinet. However, they're not tongued - they're slurred

. Being a string player by nature, you might not have any experience with a wind instrument....so imagine for every note you write, your tongue has to hit the mouthpiece...which makes those 16th note runs very unpleasant. Slurring them, however, in groups of 4, (or even slur two/tongue two, like in the Weber concertino runs) is much easier for the musician, and will sound better too!
3) I found it hard to catch the main themes in the piece overall. I felt like the entire thing was pretty static in terms of where the chords went. It wasn't very interesting, and certainly could display the clarinet better.
I say try and rework it! I think it has potential

. Also, explore the lower register of the clarinet - Anything below a middle C sounds very rich and dark, providing a great sonority for various types of music. I suggest listening to the Poulenc sonata, mozart concerto, copland concerto, and hell even the stravinsky's three pieces and Weber concertos - you'll see a vast usage of the clarinet's registers and techniques
Hope that helped!