Another 460 CC option can now be done for probably less than $20 using some custom wiring and basic switches.
I added Crawl Control using simple switches - ClubLexus - Lexus Forum Discussion
This adapter with OBD Link or OBD Fusion should get you TPMS on 4R as well. Easy plug and play and seemingly the closest to a portable Techstream I have seen. It sees into all modules and easy to throw up all your gauges for AT temps. It is also firmware upgradeable from the Link app...
They can just use current parts from the GX 460 to fulfill that piece for BSM and RCTA.
If they want to do Safety Sense as claimed on all '20 GX 460s they will need make the Driver Support package standard on all trims and pull in the pre-collision sensor from a LC/LX for the pedestrian...
Cool to hear you got your 4R converted to Crawl and MTS.
On my '12 GX 460 (which I converted back in 2/2018) it was just the replacement of the center stack switch-gear w/zero point calibration and replacement of existing Driving Support switch ECU.
DAC versus Crawl Control - ClubLexus -...
On the GX 460 with OBD Fusion this is related to the OBD adapter being used. It needs to be a legitimate 2.x ELM327 device to read this module. The cheap Chinese ones won't generally work. Check out thread here...
EDIT: Possible now for less than $20 with some simple switches and wiring.
EDIT: Successful crawl control retrofit on GX 460. Strong evidence this can be easily added to all of them.
EDIT2: Successful fit of MTS with options to add Front and Wide view monitor/camera system. / Less than...
'10-13 models have two trims - base & premium / the latter have rear air suspension
'14+ three trims - base, premium, Luxury
'10-13 Premium = '14+ Luxury
On Freeway I can get up to 21 MPG with my '12 GX 460.