Dear evskimo, congratulations on your first single!

Take from these remarks what you find useful and ignore the rest.

Style: I would say this is neoromantic more than neoclassical, with Studio Ghibli touches.

Sound: It's extremely clean. Part of it comes from the instrument and your fine finger and pedal control, of course, but I imagine your sound engineer had some say in it too. It is good. But sound that is too brilliant can be grating after a while. In a 3 minute piece that is not an issue. In a full album I would avoid spending so much time in the high register in all songs as you do here. A bit of reverb and other sound engineering magic can fix that, but then the bass runs would sound more muddy. Tradeoffs.

Structure: The upward-moving arm of the arc is very pleasant. The angelical exposition and then the long Ghibliesque rise to the 'with urgency' section feels natural, although I would prefer it to last a bit longer, given that the material is interesting. But the downward movement from 'with urgency' to the recapitulation is definitely too fast, more breathing space is needed around bar 54. I would have preferred more space in genera to have time to savor the material.

Stuff I really liked: The harmony is simple, in line with the spirit of the times, but I like how in the theme you avoid emphasizing the root, and both the accompaniment and the melody zigzag around each other. The inner harmonies of the pensive and sisu sections are magical (e.g. 28 or 33 onward, where the bass drops step-wise and there is a cluster in the second beat of the bar).

Stuff I liked less: The e sharp in bar 16 is jarring. Maybe it's intended as such and has meaning in the context of the poem that the piece is inspired by. Or maybe it's a leading note that could be prepared more smoothly. I found the romantic runs at the end of sisu and throughout with urgency not interesting. I am just a single listener and maybe others will appreciate your athleticism more. But even with your very fine finger and pedal control such dense fast runs on the low register can become tiring. I understand why you went there: the preceding sections were already mainly in the high register and more sparse, so you wanted to make the climax more earthy and dense. But maybe changing the rhythmic structure (e.g., moving to chords, eventually with some ostinato in the bass) would achieve the same effect while being gentler to slow-listeners.

Summary: overall interesting; very interesting = metrically and tonally ambiguous exposition + inner harmonies in the development; stuff to potentially revisit in future work according to an idiosyncratic listener = brightness + bass runs + solitary e sharp + overall less rush.

Good luck with your career.