mhhh "base direction" seem explicit,
an Heading will not do the job because you can be banked 60° right with 40° AOA
in this case an "heading" value will be useless (while your nose isn't the same heading than your
trajectory), in contrary a "Base direction" will show you 0° meaning your right over the target and
it's time to reset banking.
Also you have already an heading indicator on the main hud, the purpose of "base direction"
or "base slip angle ???" is to help aligning your trajectory when at high speed you try to correct
while banking left or right with an AOA >0°.
This indicator is missing now because you need to bank at 0° to know if your trajectory is right
(And I don't like at all the landing MFD)
"Base slip angle" would be more explicit ? (you know better than me, that's your language
Dan