Hi perfect_pitch
First, I enjoyed listened to your Petrushka. At the slower tempo it's amazing to hear the details in the piece! I think you've made fine progress. You've got those scalar leaps in the LH under control too. Regarding increasing the tempo, here are some thoughts:
1. In practice, for a change, whatever is legato, play it staccato, and whatever is staccato and nonlegato play it legato. This should provide you an even surer touch which will be more conducive to faster playing.
2. Try metronome drills whereby you nearly imperceptibly and incrementally increase the tempo, only two or three notches at a time, so as to fool the brain into thinking that there has been no increase. (Don't actually play with the metronome, just get the higher tempo and play.) When you start making mistakes, make a note of the setting and go no higher. Isolate the place(s) where the breakdowns occurred and give them intensive therapy. At the next session, start working the tempos upward again.
3. The movement is marked stringendo (accelerate the time) with a marking of MM = 100. However, when many composers played their own works, it's suprising how many proceeded to ignore their own metronome markings. So perhaps you only need to approach 100, but not necessarily attain it. I do understand performance practices, but then again there can be some latitude for reasonable interpretation or variance within a tempo marking.
4. Play fast music to the extent possible with flatter rather than curved fingers.
5. When it comes down to it, just will it to happen!
6. Remember, in the end it's far better to play at a tempo considering your own technique that allows for accuracy, musicality, musicianship and artistry, rather than having the piece suffer from too fast a tempo. This becomes the artist's judgment call on where to draw the line.
I hope there is something here that will be helpful to you in your quest. Good luck and keep practicing!