It really depends when/if you are planning to get a WiiU. If you plan to replicate what you are doing with the Wii, getting one once a new exclusive Zelda releases, I would probably get a Wii now and wait several years for a WiiU. It helps that now Wiis are pretty cheap here in the U.K.
Judging by your game collection, I would also get the following:
Xenoblade Chronicles
The Last Story (once it launches)
Fire Emblem: RD
Monster Hunter 3
Super Smash Bros Brawl
Both Super Mario Galaxy games
Resident Evil 4 (you have it on PS2, but I recommend the superior Wii version, it is also really cheap now)
Dragon Quest X (when it launches, however I wouldn't be surprised if it only sees a WiiU version here)
You can also use the Virtual Console to play NES, SNES, N64, SEGA MD, etc games that you might have missed. As you seem to be into JRPGs and SRPGs, I would recommend:
Ogre Battle MotBQ (SNES) and 64 (N64)
Final Fantasy IV/II and VI/III (SNES)
Chrono Trigger (SNES)
Super Mario RPG (SNES)
Paper Mario (N64)
Phantasy Star IV (SEGA MD)
Shining Force 2 (SEGA MD)
Secret of Mana (SNES)
