I would like if they did something with a sound indicating how you should read their voices before text pops up, but that's as far as they should go.
A part of what makes games like Legend of Zelda and Animal Crossing so appealing is that they're story centered with variable characters judging on how you perceive the text. Genuine voice acting kills that.
But for example, when Ganondorf comes out you hear a growling "Muhahaha" showing that we should be reading his voice in a grisly dark tone. The voice is augmented in our head for aesthetics, but it's still OUR voice.
I love solidified characters in movies and certain games, but Nintendo knows how to keep its charm, and voice acting isn't how you do it. Look at Metroid Other M.
The Pokemon franchise isn't the kind of series that delivers intense bonding with characters in general, but it definitely has the potential to. It feels like they really shot for it with the 3rd Generation with Wally and May, they just came up short.
They could do it like Fire Emblem Awakening, just have NPCs say short sentences. Like, "Oh hey!" "Look out!" "Thanks!" And etc
Voice acting would be great. Pokémon saying their names isn't canon in the games so worries about them are unfounded. The reason why Pikachu says his name in Yellow is because it was a special edition based on the anime. Anyway, Pokémon have had voices since the first game and their cries wouldn't change, they would only improve in quality. Regardless, voice acting here would apply to characters, not Pokémon. I can certainly see it during cutscenes and special cases like the PokéStar Studios.
I don't think voice acting works very well in games with mute protagonists...
Player characters have never been silent to begin with. They say things like "Go! [Pokémon]!", "[Pokémon], switch out! Come back!", "You're in charge, [Pokémon]!" and "You're foe's weak! Get 'em, [Pokémon]!"; also don't forget about the huge amount of talking they do in PokéStar Studios.