I do think the left hand gets a bit repetitive, yes. I mean, the exposition, development, recapitulation, and coda, all have that staccato motive in the left hand. Also, I listened through your first movement and looked especially at the fugato. And the fugato, as it stands right now, I couldn't play it if I tried. There are a lot of 10ths in there, in both hands. If a 10th is between a right hand note and a left hand note, I can play it. But if they are in the same hand, I have to adjust it, maybe if I can, change which hands play which notes, otherwise, I tend to omit the top note of the tenth, especially in a chord and shrink it down to an octave so that I can play it with 1 hand(a great example of where I do this is in the F minor chords of the Liszt transcription of Beethoven's fifth First Movement, I get F, C, Ab in the span of a tenth in the sheet music, in practice, I play F, C, F in the span of an octave so that I still get that F minor feel without straining my hands, possibly with an Ab below the C if I desire)
Somebody with Liszt size hands that can easily reach 10ths or 12ths would be able to play your fugato as written. I on the other hand, can barely reach a 9th on the piano(and even when I have to, it is a bit uncomfortable), and for some notes it is worse than others(For example, Bb, I would be lucky to reach a B natural from that note, whereas C, I can reach D from relatively easily). My maximum comfortable interval and the interval that I try to stay within in a piano arrangement or composition is an octave. I can definitely hear the Mozart inspiration in your sonata, but it doesn't sound 100% Mozart. I can hear your own style in there too.