I have a similar setup, and ran into storage problems pretty quickly. Eventually I reflashed it and installed Linux natively, and got a fast 64GB SD card for my home partition.
A 128gb usb drive costs very little now.
I have the Samsung Chromebook 2 (Exynos CPU, 4GB of RAM, and 16GB of storage).
I tried using a Class 10 MicroSD card to hold an Ember-CLI project, and running commands on it was intolerably slow.
A drive 4-8x that size would be nice (and not hanging off the side of the computer).