One thing I'd like to see from Sequential now is a replacement of the P12
The new filters in the PX scream to be used in another type of digital front end kind of synth... Personally I'd like to see an FPGA digital front end, that has more than just the oscillators in the FPGA... I like the idear of the analog filters, but they are only LP, so if they instead included some unique digital filters in the FPGA it would become rather interesting, plus more ways to modulate between the oscillators than just the usual sync, ringmod and FM... I'd like to see some filter types that are rare in the analog domain like formant filters, waveshapers and other fun stuff that will allow you to get a really huge timbral range before the conversion to analog. I also hope for FX where the reverb has more modulation options than the current synth range... preferably I'd also like it to sport 4 oscillators so that the synth could have a built in joystick for Prophet VS type of performance where you can mix between the four waveforms (or other parameters) using the joystick.
Also... I'd like waveform storage like it was on the Evolver... with todays huge amount of memory for cheap, it should be possible to make a huge waveform bank with say; 4096 single cycle waveforms that you could upload yourself via SysEx, and then use these for both oscillator waveforms and LFO waveforms.... I'm thinking that the wavetables could be done a bit like it was on the P12 where you chose a left/middle/right waveshape, but just expand this to 5 waveforms instead that you can morph in between... this is what I miss on the PEAK because the wavetables are ROM shapes, not RAM which would greatly expand on the sonic pallette.
All in all I'd like to see a more wavetable oriented hybrid synth from Sequential.. .especially with FPGA for the digital part, with a joystick to use as performance controller.