For one, I hope I didn't come across as if you should change anything. It's pristine as is; anything I'd recommend would just be ideas to consider for future endeavors.
One of the reasons I liked your piece so much was the craftsmanship with developing your material. The whole ta ta ti ti ta thing I think comes from me teaching guitar, and that's the go to strum pattern I use to start people out. It just sounded a bit rough with the hard attacks from the strings to me. I think it was the development section that starts off with that phrase sped up and works wonderfully. It's like this: You and I go get ice cream. You pick chocolate, I pick vanilla (let's say...ta ta ta ti ti). I like chocolate too, but prefer vanilla, and we're both happy.
This was directed purely at the orchestration and not it's content. I expected Shosta 5 at the end, but you still nailed the effect.
Yes there is! You provided so much content, but not so much context. What's this about? Anything in particular? Covid? A new beginning? A sex change? I'd love to hear.
Also, I think a title of Sinfonietta fits, but I'm curious what your intentions are with it. Do you plan on having it performed? Is it feasible wherever you live? This shouldn't matter, but it does: who are you trying to reach with your music? Would your friends and colleagues and family be more intrigued by your music if it had a more unique title?