You will have some cross over. I.E. Technical support could go under tech or customer service. If you are a large enough company, tech support would become a group. If you are smaller they would probably go under Tech but close to Customer Support. A word on titles.
Titles are cheap.
Make them up. Whether there is management responsibilities or not associated with them, its a morale thing. CTO of a 4 person company may not mean anything to the world, but may mean something to that person. That builds a span of control of 3 for the supreme being. Once you have the groups split, ideally you would figure out who would head up the groups and enlist their help in deciding if those groups have to be split up further.