Hey Markus, I haven't seen you in a while, glad to hear you're still writing π
I love these kinds of posts. It's really cool to hear your problem, then for me to try it out and mess around on it. Thanks for posting your thought process, as I can start with yours and see where that takes me.
One idea I had was to let the clarinet be a pedal point for the E7. I had F for the "Dm" chord measure, but it didn't sound good to me. I liked the absence of the clarinet here, so maybe keep it simple if this thought leads you somewhere.
For me, it helps to see the entire 4 bar phrase as E7. I know that one spot is tricky, but it just seems like a big cadence to Am (Also, this whole transition from Bb to F is wonderful and very smooth. Is it Am - C7 - F? I like the iii - V7 - I movement). If I look at it as E7 with a bunch of chromatics, it's easier to think about the clarinet. I came up with this pretty quick, I'm sure the notes could be tinkered with. I don't remember, but little rhythmic motifs you may have used could go well with the clarinet, I just came up with something simple.
Oh, and our music player sucks lol. It's hard to go to a certain spot within a piece, so I think I've heard the first minute or so several times π
Hopefully some of these thoughts are useful π
Great stuff, keep us updated!
P.S. The bassoon starts on B nat. right?