You really don't need voice chat beside social stuff.
I know a lot of newcomers are jumping into the series with MH4, but there has never been and likely never will be a voice chat feature in MH -- at least not on a handheld system. The series is almost as conservative as Pokemon. Its also not needed and I would argue that even for the harder monsters.
Edit: And just to note both of you that I quoted... It's always been a hugely social game hence why before the Wii, PS3, and WiiU versions the game had pretty much exclusively local multiplayer meaning that players were within talking distance if you wanna tell me that those players didn't communicate at all because they are so "veteran" or "pro"...
I mean really communication has always been needed for the series but voice chat hasn't. I'm sorry I'm a huge fan of the series and a "veteran" but I wont go around acting like features are not needed or wouldn't be nice.
End Edit
Hardly a newcomer to the series but it was nice to have voice chat in MH3U on the WiiU and it doesn't make much sense why it couldn't carry on onto this as well.
Other 3ds titles have voice chat through the mic, it's not a standard but it does seem like an oversight as it was a feature of MH3U. And it's always fun talking with the friends you're playing with to communicate in the fly, it would be nothing but plus to have.
And it is a shame they left it out regardless of how long you've been a veteran of the series. While core gameplay makes this game as great as always certain newer features would help.