Evening,
Simple answer nothing wrong with running vCSA on a single ESXi host and manage that host with it.
Long answer: it depends 
What features of vcenter are you planning on using... perhaps a vDS? (there are some chicken and egg issues with vDS and vcenter availablity).
Let me know what features in vcenter you plan on using on your single host and I'll let you know if there are other problems.
Thanks,
J