I pitched "sysadmin as a service" to a sysadmin friend and he was totally against it. He said we don't need more sysadmins, we need better developers who understand sysadmin fundamentals and know how to build stable systems. How about taking both and synthesize them? Sysadmin-as-a-service + training and education service. Hire the consultant for the bandaid fix of the immediate problem and to train and help educate the internal team on the sysadmin fundamentals they are missing.