The TG16 has great platformers and shooters, but really lacks in RPGs. You need to go to a TurboCD or TurboDuo to get any good (or awful) RPGs.
The often advised cheapest method to play anything is to get a region modded Japanese Duo. However, before investing, make sure you really want to play Ys 1-3, Exile, or Cosmic Fantasy 2. You are still going to spend around $150 more for the Duo, than you would for a TG16, and there are tons of good shooters and platformers on the American TG16 to fill your needs.