Hi Jamie,
There is only one iFlow for Employee Central, the Employee Central Mini Master (see http://service.sap.com/ec-ondemand for the documentation) which is within Boomi. There is also a component on the SAP side for Employee Central Payroll (PA_SE_IN 100).
Unlike the other iFlows, there is no specific package as the iFlow is within Dell Boomi AtomSphere (e.g. with your subscription it will show within Dell Boomi AtomSphere and doesn't need to be loaded).
There's no published roadmap per se because of the short release cycles.
See you at SuccessConnect?
Best regards,
Luke