Using an Alinco dj-c5t, a TTS-03 TextSpeak™ Module, and an allspice node running custom software it should be possible to create a fun and interactive voice radio onboard the balloon to talk and spell out current events to be tuned into by the amateur radio community.
The main obstacle is cost, and private funding may need to be sought after as this is not a mission critical payload. Repeaters could be used to extend the range with the permission of the repeater owners (KBARA for example). For repeater usage, the messages should be few and far between and squelch should be checked before transmitting.
The alinco radio provides 300mW operation in a tiny package which runs off of a single lithium cell. This cell could power the entire setup, including the allspice node and the text to speech module.
Note : http://www.acroname.com/robotics/parts/R184-SP03.html is a cheaper, smaller text to speech engine
