Note that you still can't go directly to B. You must go through D then to B! Big bummer.
If the shifter on our Rav4 EV is anything like the one of the similar gen prius then this Mod could work for us who want to push buttons instead of shifting.
Best part is that it appears to take only 5 minutes so plug and play!
I hear it is faster to switch gears and more comfortable. I personally find it annoying having to go through D to get to B and sometimes if you do it too fast you get a beep in that it fails, or I failed to shift properly. Not that common but it does happen and it is annoying.
Also just staying on B can be tiring for the foot 
though really staying in B gives you the most control!
This button shifter mod could make it all much easier.
Google "prius electronic switch shifter" for more info
https://www.amazon.com/Intelligence-Position-Switch-Toyota-2010-2013/dp/B00TZY4OMW
There seem to be a couple of options. In ebay I see a few being sold too. Search for Prius Electronic shift switch
http://www.ebay.com/sch/i.html?_from=R40&_trksid=p2047675.m570.l1313.TR0.TRC0.H0.XPrius+Electronic+shift+switch.TRS0&_nkw=Prius+Electronic+shift+switch&_sacat=0
ELD produced by C-WEST, TOYOTA PRIUS ELECTRONIC SHIFT SWITCH BLUE for RHD
JDM TOYOTA PRIUS TOM'S GENUINE LED SHIFT KNOB SWITCH
STAGE 10 ESS PRIUS Shifter
https://stage-10-online.myshopify.com/
OGS Intelligence Position Switch for Toyota Prius 2010-2013
