Nope, other sales won't improve by much..

I don't think so.

Don't think it makes much of a difference either way.

Only Xenoblade Chronicles X would probably get some sales that would have otherwise went to Zelda Wii U and that is only if it is released outside of Japan this year. The other potential games, Star Fox, Devil's Third and Splatoon aren't likely to directly benefit from Zelda not being released besides maybe Nintendo dedicating more resources to their promotion.

Maybe Xenoblade, all I can think of

Probably not, Nintendo has so few games releasing they were proabably gonna spread them far enough so they don't affect each other.  Its not like the PS4/X1 where you have multiple AAA games releasing so close together during the holidays and its overload for some gamers.