This post is very interesting.
The scenary that you are drawing for a small business of 10-30 people is something like that: a file sync layer (like dropbox for business) that replicate everything locally, eventually on big'n'cheap ssd (compared to costly enterprise storage), so remote offices wouldn't be a problem. This way, is possible to leverage all the power of modern hardware (even a core i3 of the latest gen has plenty of power), without the hassle and the big uprofont investment of phisical servers, thin clients, storage etc. Every other service that canno be served in a SaaS way, of course can be hosted in a IaaS (I'm thinking about the typical windows-based ERP) and connected via a router to the local network.
So, the shopping cart to start a full-fledged IT infrastructure in SMB should be composed of just switches, a router with vpn capabilities (edgerouter er8?), desktops with big ssd (AMT - vPro) and a bunch of services like AWS, office 365, dropbox for business etc.
Maybe 1000-1200€ per seats (every 4 years) plus 30-40€/month/user… not bad, considering that one of the SMB in which I work bought upfront 70000€ of servers/storage/vmware/windows server tl… I'm afraid, with less performance and reliability.