Yes to both. Mp3 files are very small, just a bing or a bong (< 2 secs). Max is 10 seconds long but is called very seldomly. Cepstral Swift I call via an exec node by sending it (msg.payload) of what the computer needs to say. Other then a weather forecast (once per day) these are less than 5 second voice msgs. I have learned to watch swift and memory use closely. As a side note, NR has failed when I've been away for a week and no voice messages would be processed, which is why I went looking elsewhere for the culprit.
I also have an Arduino NANO .that monitors the solar battery bank voltage, battery current flow (+ or -) and commercial hydro sense. These provide an update to the rpi every 1/2 second via USB.
