It really is a lovable piece, especially the beginning, having the aura of Chopin's nocturne. The agitated middle section is also effective enough. C sharp minor is my favourite key and I love almost every piece in c sharp minor.
I wonder if the time signature of the slow section should be 3/4 time rather than 6/8 time, because I feel like it's more in simple triple meter rather than compound duple meter.
I agree with @Omicronrg9that it's weird to change key just for a few bars.
I agree with your reflection that the agitated passage can stay longer in g minor to provide more contrast, because it can create a dramatic with the neapolitan chord of D major suddenly reinterpreted as the dominant of g minor. Another option for me is just don't modulate to g minor, because I already find the agitated passage from bar 49 onward in the original key of c sharp minor enough to provide to provide contrast with different mood, meter, dynamic and texture. But it's up to your intention.
I think the effect is dramatic and good with clear intention and knowledge of modulation and harmonic progression, only the passage in g minor is too short.
For the chord progression from bar 61-62, I will put the full dominant chord of c sharp minor, G sharp-B sharp-D sharp-G sharp in high register of the right hand, since it's more dramatic. But that's only my personal preference, since the lone D sharp also creates great effect for being lonely and in solitude.
My favourite part of the piece is the slow sections, because it is my favourite key!!