I like the idea of turning into a shadow as the capstone for the shadow dance. Stack on some resistances and extra rules as discussed above and it seems very cool. Are we still talking about framing the dance like the Bladesong. so it lasts for a minute and can be used X number of times per day? I like that idea a lot.
On the ranged weapon thing, I still disagree completely. The PHB defines ranged as applying to a weapon has has a range listed in parentheses and either the thrown or ammunition property. Ranged doesn't define the weapon, just the capability of making a type of attack: the definition of ranged weapon is "used to attack a target at a distance". There is no section of the rules that treats weapons with the ammunition property as different from one with the thrown property as regards attacking at range, and indeed both types can also be used to attack in melee. The only place in the book that even partially supports your reading of the RAW is the organization of the weapon list. The list doesn't supersede or replace the definitions or descriptors though. The list does not define the weapon, the properties define the weapon, and the properties of thrown weapons define them as ranged weapons in exactly the same way they define weapons with the ammunition property. There's nothing wrong with my reading of the RAW.
Try to define ranged weapon using the rules, but without reference to the weapon list and you'll see what I mean.