D&D 5E Elves, Wizards, Sorcerers, Charisma

[Nivenus]

True. I'd say INT 18, WIS 9, CHA 16.

That sounds like it's in the ballpark. His Intelligence is obviously pretty high and his Charisma seems formidable as well, but he does have a tendency toward some really foolish actions from time to time that don't serve him well in the long-term.

 

[Skyscraper]

Your idea is as good as any. If you feel that your game would be interesting with it implemented, go ahead and do it!