I think the ki sensing should work like this:
The color of the "dots" would represent how powerfull a person you are sensing, not necessarily who your are sensing. In the show they never knew who they were sensing, they just sense the person's ki. I think the colors should be the same as the auras. Like a white dot is weak ki signiture, blue is medium, red is powerful, yellow is most powerful. A flashing dot would mean who you are sensing is transforming. Of course there should be different shades in between colors so you can recognized the power more accurately. If this is ever implemented, I think it should replace the overhead radar for the scouter, but only for detecting other people (It should still be used for finding dragonballs, just you wouldn't see the other players).
Oh, and i see the "ki sensing" as two radars, one representing what is in front of you and one representing what is behind you. If anyone here has ever played any of the X-Wing or Tie-Fighter games then you know what I'm talking about. There is a radar on the top right of the screen representing everything in front of you, and one on the top left representing what is behind you.
And also, people should be able to "suppress" their power level to hide themselves from being sensed. In other words, if you want to sneak up on someone, you "hide' your powerlevel, making you weak, which is the drawback, but the advantage is you dont show up on anyone's ki sensing radar. You should, obviously, be able to power back up to full strength, but of course they will sence you.