[clairity]

yes, that's the best split--make frequently-used features and/or features used primarily while driving physical controls, while rarely-used features and/or features used while parked can be touch-based.

however, address input should be primarily by voice control rather than touch entry. changing destinations (for whatever reason) mid-drive on a navigation system is dangerous and somewhat common, and voice control is the best option for keeping your eyes on the road (absent a passenger who can do the touchscreen data entry).