Associative or hash arrays would be a big improvement over the existing lists in that elements could be accessed by something self-documenting like "TrueAnomaly" instead of an index number.
This would allow transmitting more rich information between part scripts while keeping things more sane.
It would also allow one to create the equivalent of multiple variables of the same name but in separate arrays. For example ActiveCraft["TrueAnomaly"] and TargetCraft["TrueAnomaly"] and common code that could handle either. Of course ActiveCraft and TargetCraft could also be updated many other common keys, or variables, related to the craft, like "RollAxisPCI", "DockportAxisPCI", etc.
These arrays could be passed via messages within or between craft just as lists are.
It would allow for faux localization of variables.
The functionality could be layered onto the existing List type, or a new separate type could be made. There are solid reasons nearly all modern scripting languages have some kind of hash, lexicon, or associative arrays and Vizzy would benefit for the same reasons