The lowest string is much louder compared to the highest one, so for example if you could select a range of notes and add a custom velocity boost to it. Struck note velocity + custom number velocity boost added automatically for selected note range. Does that makes sense? 
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I often encounter this problem with different variants on different vsti’s and have always managed to balance the dynamics from low to high using the parameters in the Midi Velocity window. It takes a bit of juggling between the 3 parameters to get a good result and I have never encountered a case where I had to go further and create a script for this.
I’m convinced that the script you’re thinking of would end up with this Midi Velocity window with at least the first two parameters to manage the range and the third to adjust the dynamics of the whole.
Read page 6 of the help if you have never delved into these settings .
Now, if that is not enough, yes: more scripting is always possible - at least not for me who doesn’t know enough about scripting. 
I’ve tried a lot of different combinations with those 3 buttons, but when I fix one problem another occurs. The settings are pretty good when they’re set at 12 o’ clock, but it’s very hard to incorporate these types of two hand tapping licks. I can’t balance it out so every note has the same loudness. Even if I do manage to somewhat balance it, when I go back to normal playing everything else sounds off.
I’m sorry I can’t help you more, especially as I don’t understand the image you posted - I don’t read or write music, I leave that to a software
I assume you play all the notes with the same attack, but perhaps this should also be taken into account depending on the instrument you are playing.
Apart from the Midi Velocity settings, I attack low and high strings differently for e.g. a cello or a saxophone…