A couple of extra thoughts:
By having the Chromebook in the office, I can get my "internet fix" without utilizing my office laptop and main computer for this function. This will add an additional layer of security.
Almost all attacks ultimately are OS based, so you insulate yourself from 99% of the existing attacks.
Thinking off the cuff, but having one or two of the Chromebooks in the break room for staff use, may decrease the risk of inappropriate internet surfing while working. Allowing use of the Chromebooks in such a fashion, for a minimal cost, may reduce the likelihood of malware or virus introduction into the computers designated for work.
Any one doing this already or have any other thoughts?
This is the least expensive way to protect your practice from infections unless you implement an edge device(router/firewall) that proxies your internet and filters content.
One of the benefits of a more advanced edge device is that you can get email alerts on infected download attempts of unauthorized content [e.g. FaceBook, Youtube, p0rn)