Regular Allomancers "see" the lines as coming out of the center of their chest, but they "see" them with their eyes. Inquisitors were human once; they probably perceive it the same way.
So the blue lines always come out of your chest, and you perceive them from the perspective of where your eyes are? That would actually fit quite well. (Now I want someone who was born blind to Snap into a Lurcher or a Coinshot, so they don't have preconceptions)
Some more powers that I found/remembered:
Brass/Zinc: control Hemalurgic creations
Bronze (with Duralumin): Know exactly what is being done with Allomancy. (Vin hearing Breeze Soothing Elend)
and some more questions:
Electrum: can you use it to find out your capabilities? For example, if you run at a gap between two buildings while burning Electrum, would you see all of your shadows fall into the alley if the gap was too wide for you to jump? This would allow you to stop running in time. If it could be used this way, then it could be useful for seeing where you will land with a steel jump.
Brass/Zinc: can they be used to control only Hemalurgic creations (Inquisitors, Koloss, and Kandra), or anyone with a spike? It would definitely be more difficult the fewer spikes are in someone/something, but is it possible?