I get the feeling that sales of Virtual Console games had slowed way down, which is why they started trickling them out and don't seem them as a priority anymore. It's also probably a part of why Nintendo are more focused on bringing new content to the VC like Earthbound and GBA games instead of converting over the Wii catalogue, which is technically still playable on a Wii U so Nintendo figure that's good enough.
What I would like to happen are these things, most of which I think won't happen:
-Get the entire Wii library on Wii U.
-Make a unified VC across 3DS and Wii U for all games that can run on 3DS (NES, SNES, and Genesis should work, not sure about GBA, supposedly the 3DS has a hard time emulating it when still running the full 3DS OS). So if you buy an SNES game on Wii U, you can also play it on 3DS at no extra cost. Buy a Game Boy game on 3DS, you can play it on Wii U too.
-No fees to transfer/update games to the next systems.
-Add netplay. Currently I don't buy VC games, but I totally would if they had netplay.
-Add Game Boy Color and Super Game Boy features to GB VC games.