Create a new Nintendo Network ID

I'm not quite happy with my NNID I registered initially, and I want to change it. I'm planning to register a new NNID user, unlink current user from Nintendo Club, link new user to Nintendo Club. As far as I know I still will have access to all purchases I've made using it, while old user will be registered on the system.

Is there some other potential problems I'm missing?

So, I've completed operations as planned and everything seems working as expected. Suppose you want to use new NewName as a primary NNID instead of old OldName with a possible minimum impact.

1. Register a new NewName user on a console, and follow standard procedure of creating new Mii and NNID. You can use same email as for OldName user.
2. Under OldName user, launch eShop and unlink Nintendo Club if necessary.
3. Under NewName user, launch eShop and link Nintendo Club if necessary.
4. Under NewName user, in user switch menu select Make Default.

That's it! You can still access all purchases made under OldName. Of course you lose all information associated with old account, most notably including save games (however some games have shared save files which are user-independent), friends and all Miiverse data. But as long as you keep old user you can always switch back to access it.