However, knobs underneath sliders is never a good idea - it restricts access to the faders and thus is not very ergonomic.
I also agree about the ribbon, I would possibly add a ribbon like on the Alesis Andromeda directly underneath the pads. that would actually add some neat possibility to tweak cutoff or pitch with the ribbon whilst playing chords on the pads!
also, you forgot to change the screen to say M10.
don't forget the EXB-CX4 and EXB-MSradias
Current Gear: Kronos 61, RADIAS-R, Volca Bass, ESX-1, microKorg, MS2000B, R3, Kaossilator Pro +, MiniKP, AX3000B, nanoKontrol, nanoPad MK II,
Other Mfgrs: Moog Sub37, Roland Boutique JX03, Novation MiniNova, Akai APC40, MOTU MIDI TimePiece 2, ART Pro VLA, Focusrite Saffire Pro 40.
Past Gear: Korg Karma, TR61, Poly800, EA-1, ER-1, ES-1, Kawai K1, Novation ReMote37SL, Boss GT-6B
Software: NI Komplete 10 Ultimate, Arturia V Collection, Ableton Live 9. Apple OSX El Capitan on 15" MacBook Pro