Which hotel did u stay at? I saw some nice reviews & pics for Hilton but I'm not prepared to part with 3grand per night
How much did a taxi cost from your hotel to stone town?
I've stayed at the Doubletree Hilton in Nungwi on two occasions. We found specials online both times. I'd recommend it, but R3K per night is pushing it.
The best place to swim with dolphins is generally said to be Kizimkazi. We did get to swim with dolphins there but it was about a 2 hour long drive from Nungwi in a really sh1tty taxi, and I wouldn't say it is worth it as we got to swim with some dolphins again on the way to Mnemba island.
Spice Tour I'd rank last of the tours to choose to do. Mnemba Island #1, Safari Blue #2. Stone Town and Prison Island you can do on the same day. I would not waste a night staying over in Stone Town again.
My last 2 trips to Zanzibar I've rented a car. You get to see so much more and it's not expensive. Just be prepared for the corrupt cops who want cash bribes.