You don't have to use the CA to get torque sensor functionality with the BR; it directly supports them according to the BR page:
The Baserunner is a slim profile field-oriented motor controller that fits inside the baseplate of popular downtube battery packs. This product is based around ASI’s BAC355 controller platform ,but is configured and connectorized to be much easier to wire up in an aftermarket ebike.
ebikes.ca
 | 6 Pin PAS / Torque
A 6 Pin HiGo Mini-B or equivalent waterproof plug allows for direct hookup of a PAS or Torque sensor to the motor controller. The pin standard is compatible with the ERider torque sensors, and uses 12V rather than 5V for the power supply. This cable is not used or required when PAS or torque assist is handle via a Cycle Analyst, but it will provides a future option for using the native PAS feature of the controller without a CA device attached. |
Once they release the Main9 Superharness kits they emailed about back in December, you can use 3rd party displays on the BR, including various "colorful" ones. Dunno when that will be as there wasn't a date in the email, and nothing on their blog about it yet.
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If for any reason you want the other CA functionality, you don't have to put it on the handlebars--it can go wherever you want it, in a bag, battery box, etc. If you need to change settings on it (presets, assist levels, etc) you can use remote buttons or knobs to do this; see the CA pages on their site, and the CA accessories in their shop for options. (you can also build your own controls to connect to the CA based on the info in the manual).