Have you tried rearranging the layers so that the lineart layer is on top and not the color layers? Then you can set the layer blending to "multiply" and it makes the white in the outline layer disappear with no effort. Just put the color layers underneath.
It's how I used to color my scanned drawings before I finally managed to procure the tools that I need to efficiently redraw the outline on the computer.
After you've done that, lighten the outline layer slightly or color it a little to make it look better.
I use photoshop almost every week and I don't understand what the hell are you saying (Probably because mine is in spanish... )
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there is no time be emotional! 
Wow
)
