So from a hobbyist view point:
Cost,but not penny pinching so I am unhappy out of the shoot and upgrading right away
I love the delta design point but I would like to see a larger base but not necessarily a taller build.
Some level of enclosure for the build chamber (printable so it would be a 'free upgrade' )
Some real auto calibration with one-time ( well not-very-often ) manual bed adjustment.
32 bits processing power
I would like the 2-1 print head (Hey CA for dual independent extruders, did you see this https://www.thingiverse.com/thing:1087944 )
Fast SDcard write via either wifi or USB

Just my thoughts