I'd love to see more features on the Purion, but I'm pretty sure it's maxed-out in terms of what it is capable of. It doesn't even have a clock/calendar, and most areas of the Purion screen are not configurable (they light up a pre-set symbol or text.)
The Purion & Intuvia were never designed with eMTB in mind, as a result the firmware for the display needed to be changed on both.
The Purion with regards to displaying assist modes would have been an easy change - display eMTB instead of Sport.
The Intuvia is different as it's assist modes are hard wired on the screen, so the Sport display item is turned on (as without eMTB) but extra firmware code added so as to briefly display eMTB on the screen as well.
The size of the firmware code within the Intuvia GREW to allow for eMTB.
The size of the firmware inside the motor GREW to allow detection of "Tampering" & how many "Tampering" incidents have occurred.
I'm sure if the ebike connect app could communicate directly with the USB ports of Purion, Intuvia, Kiox or Smartphonehub then it should not be impossible to add Lock, Cadence & Custom Ride modes to these displays, also firmware updates.
Sure the Lock may behave differently on some displays & motors (not be tied to a phone/whatever), a user defined key combination to lock/unlock for instance, configured with the ebike connect app, using up perhaps 8 bytes (not Kilobytes, not Megabytes) of data memory in the motor or display.
Custom ride modes could be toggled on the Purion & Intuvia by a quick simultaneous press of + & -, the Purion uses a long simultaneous press of + & - to Reset trip distance but neither use a short press + & - combination - using up perhaps 20 bytes of data in the motor (4 modes x 5 check points - 1 byte (256 levels)).
Each time Custom ride modes or ride modes are changed it can flash the word "Custom" briefly, just as the Intuvia does for eMTB.
There may be a limit to how much the firmware can grow within each display & the motor and would be an easy way out if Bosch could not be bothered to do any of the above and what others have been asking for.
And charge up to four times the price for these features when using a Purion or Intuvia, or not at all, i would pay up to four times the price for this and i'm sure many other existing Bosch customers would too.
Not much is impossible with a bit of software.
Or just spend more money on an updated system?