I would pick up Baiten Kaitos for 15 bucks used, maybe Fire Emblem GC, Skies of Arcadia Legends, Tales of Symphona.
The next real RPG for Wii coming is ToS:DoTNW in June. Make sure you play ToS first.
End of 2009 Predictions (Set, January 1st 2009)
Wii- 72 million 3rd Year Peak, better slate of releases
360- 37 million Should trend down slightly after 3rd year peak
PS3- 29 million Sales should pick up next year, 3rd year peak and price cut