I am glad you are enjoying the DX100. Our next dap should meet many expectations. You can never meet everyone's but we try. The next dap will be very exciting.
My wish list for your next DAP :
Supreme SQ (this we are sure that you will deliver
)
Wifi: Hifi Streaming & download from Qobuz and/or Tidal
Balanced headphone out (NO 2,5 mm A&K plug please
... Mini-XLR or TSSR 3,5 mm instead.
Enough power to drive a full scale headphone to it's best.
512 Gb Capacity minimum and if possible
FullSize SD rather than MicroSD
"REAL" Line Out ( to drive our home desktop amps )
Digital out (Optical or USB or Coax)
(VERY) Large screen and contrasted enough to be readable in the sun.
Modern UI, with full usage of cover arts everywhere (not only in the "album" mode, but also in folder and in Playlist mode)
And... don't try to make it as small as possible. Instead please make the BEST sound/capacity possible. If you can fit 1 To capacity inside, then this DAP can also be used at home as our source to drive our desktop DAC or AMP (hense a new market for you