I'd have to agree on the RETF's. They can be sensitive and tough for a beginner. Best to wait until you have a bit of experience behind you .

Another thing to think about is which species are awake during the day (diurnal) or awake at night (nocturnal). Many tree frogs are awake at night. Dart frogs and fire belly toads are awake during the day and are fun to watch. Both species are energetic and entertaining.

Just a thought .