Miiverse is probably one of my favorite parts about the Wii U, so no, I wouldn't say abandoning it is an idea I'd endorse. If it could be done effortlessly, I wouldn't mind integrating social networking sites, but I don't believe it's anywhere near as important as you're making it out to be.
If anyone enjoys a game enough to the point where they really want to talk about it with their friends, they're likely going to do so whether they can instantly access it from their console or if they have to pull up the website on a laptop. The reason why not many Wii U games have been showing up on these websites is because there aren't that many Wii U games worth mentioning to begin with.
Nintendo's focus should be on adding to what's already looking like a decent second half of the year for the Wii U in terms of its games library, not messing around with social media.
