TTS does work with Overdrive and Kindle Unlimited on the Echo. The TTS feature is based on if the publisher allows it on that specific title, and most do.
TTS sounds pretty good on the Echo... greatly improved since my Kindle Keyboard days!
You can set multiple timers and alarms. Yes Pandora works with it. I just asked for the weather for Friday, and also, randomly the forecast for Edinburgh, Scotland. Next I asked for Pizza Hut's phone number. There is a 'to do' list and a 'shopping list feature.
Hm... didn't know my phone could do a Note to Self! Thanks!