hi @frbiggs I’ve used the teensy – but it comes in a number of flavors.
IHMO the Teensy3.5 also has +5V tolerant pins.
The Teensy3.5 and 3.6 processors have some nice ram. https://blog.adafruit.com/2016/10/06/new-products-teensy-3-5-teensy-3-6/
Can you say what your context is – are you looking to use ModularSensors which also has a lot of infrastructure support.