Sorry...I can't tell you (don't know) the reasoning behind the change.
The 370 doesn't have TPMS...funny, though, I don't remember being able to monitor TP from the center gauge cluster and I had TPMS on both my '07 Grand Touring Coupe and on my '08 Grand Touring Roadster...maybe that was something offered on the track and/or enthusiast models before they discontinued them???
I miss the digital speed readout but am slowloy getting used to using the analog speedomoter again.
I would say that trying to add those features yourself would be a lot of work...I also would say, as an advid autocrosser, that I wouldn't trust the TPMS readout to know what my pressure was during an event; I'd always use a very good hand-held unit for that.